diff --git a/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets b/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
index 7bbf4e613e4975..55dedda8fdd16a 100644
--- a/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
+++ b/src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets
@@ -29,7 +29,7 @@ The .NET Foundation licenses this file to you under the MIT license.
   <Target Name="SetupOSSpecificProps" DependsOnTargets="$(IlcDynamicBuildPropertyDependencies)">
 
     <PropertyGroup>
-      <UseSystemZlib Condition="'$(UseSystemZlib)' == '' and !Exists('$(IlcSdkPath)libz.a')">true</UseSystemZlib>
+      <UseSystemZlib Condition="'$(UseSystemZlib)' == '' and !Exists('$(IlcFrameworkNativePath)libz.a')">true</UseSystemZlib>
       <FullRuntimeName>libRuntime.WorkstationGC</FullRuntimeName>
       <FullRuntimeName Condition="'$(ServerGarbageCollection)' == 'true' or '$(IlcLinkServerGC)' == 'true'">libRuntime.ServerGC</FullRuntimeName>
 
@@ -166,7 +166,7 @@ The .NET Foundation licenses this file to you under the MIT license.
 
     <ItemGroup>
       <!-- zlib must be added after System.IO.Compression.Native, order matters. -->
-      <NativeLibrary Condition="'$(UseSystemZlib)' != 'true'" Include="$(IlcSdkPath)libz.a" />
+      <NativeLibrary Condition="'$(UseSystemZlib)' != 'true'" Include="$(IlcFrameworkNativePath)libz.a" />
     </ItemGroup>
 
     <ItemGroup Condition="'$(StaticICULinking)' == 'true' and '$(NativeLib)' != 'Static' and '$(InvariantGlobalization)' != 'true'">
diff --git a/src/mono/browser/runtime/CMakeLists.txt b/src/mono/browser/runtime/CMakeLists.txt
index 93be47d8d09fd9..95938c2e425100 100644
--- a/src/mono/browser/runtime/CMakeLists.txt
+++ b/src/mono/browser/runtime/CMakeLists.txt
@@ -29,11 +29,11 @@ target_link_libraries(dotnet.native
     ${MONO_ARTIFACTS_DIR}/libmono-profiler-aot.a
     ${MONO_ARTIFACTS_DIR}/libmono-profiler-browser.a
     ${MONO_ARTIFACTS_DIR}/libmono-profiler-log.a
-    ${MONO_ARTIFACTS_DIR}/libz.a
     ${NATIVE_BIN_DIR}/wasm-bundled-timezones.a
     ${NATIVE_BIN_DIR}/libSystem.Native.a
     ${NATIVE_BIN_DIR}/libSystem.Globalization.Native.a
-    ${NATIVE_BIN_DIR}/libSystem.IO.Compression.Native.a)
+    ${NATIVE_BIN_DIR}/libSystem.IO.Compression.Native.a
+    ${NATIVE_BIN_DIR}/libz.a)
 
 set_target_properties(dotnet.native PROPERTIES
     LINK_DEPENDS "${NATIVE_BIN_DIR}/src/emcc-default.rsp;${NATIVE_BIN_DIR}/src/es6/dotnet.es6.pre.js;${NATIVE_BIN_DIR}/src/es6/dotnet.es6.lib.js;${NATIVE_BIN_DIR}/src/es6/dotnet.es6.extpost.js;"
diff --git a/src/mono/mono.proj b/src/mono/mono.proj
index a9bdbb62e0afa3..cc4d240fe835fb 100644
--- a/src/mono/mono.proj
+++ b/src/mono/mono.proj
@@ -273,7 +273,7 @@ JS_ENGINES = [NODE_JS]
     </PropertyGroup>
 
     <RemoveDir Directories="$(EMSDK_PATH)" />
-    
+
     <ItemGroup>
       <EmsdkFiles   Condition="'%(PackageReference.Identity)' != 'runtime.$(_portableHostOS)-$(BuildArchitecture).Microsoft.NETCore.Runtime.Wasm.Node.Transport' and '%(PackageReference.Identity)' != 'Microsoft.NET.Runtime.Emscripten.$(EmsdkVersion).Python.win-$(BuildArchitecture)'"
                     Include="$(NuGetPackageRoot)\$([System.String]::Copy(%(PackageReference.Identity)).ToLowerInvariant())\%(PackageReference.Version)\tools\**" />
@@ -295,7 +295,7 @@ JS_ENGINES = [NODE_JS]
     <ReadLinesFromFile File="$(EMSDK_PATH)emsdk_env$(ScriptExt)">
       <Output TaskParameter="Lines" PropertyName="_EmsdkEnvFileText" />
     </ReadLinesFromFile>
-    <WriteLinesToFile File="$(EMSDK_PATH)emsdk_env$(ScriptExt)" 
+    <WriteLinesToFile File="$(EMSDK_PATH)emsdk_env$(ScriptExt)"
                       Overwrite="true"
                       Lines="$(_EmsdkPaths);$(_EmsdkEnvFileText)" />
     <WriteLinesToFile File="$(EMSDK_PATH)emscripten/.emscripten"
@@ -313,7 +313,7 @@ JS_ENGINES = [NODE_JS]
 
     <PropertyGroup>
       <ShouldProvisionEmscripten>false</ShouldProvisionEmscripten>
-    </PropertyGroup>    
+    </PropertyGroup>
   </Target>
 
   <!-- Sets up WASI SDK if you don't have the WASI_SDK_PATH env variable set -->
@@ -365,8 +365,8 @@ JS_ENGINES = [NODE_JS]
     See https://github.com/llvm/llvm-project/pull/98373
     See https://github.com/dotnet/runtime/issues/104773
     -->
-    <Exec Command="wasm-opt --version" IgnoreExitCode="true" 
-      IgnoreStandardErrorWarningFormat="true" 
+    <Exec Command="wasm-opt --version" IgnoreExitCode="true"
+      IgnoreStandardErrorWarningFormat="true"
       StandardErrorImportance="low"
       StandardOutputImportance="Low" >
       <Output TaskParameter="ExitCode" PropertyName="_WasmOptExitCode"/>
@@ -1208,9 +1208,6 @@ JS_ENGINES = [NODE_JS]
       <_MonoRuntimeArtifacts Condition="('$(TargetsBrowser)' == 'true'  or '$(TargetsWasi)' == 'true') and '$(BuildMonoAOTCrossCompilerOnly)' != 'true'" Include="$(MonoObjDir)out\lib\libmono-wasm-nosimd.a">
         <Destination>$(RuntimeBinDir)libmono-wasm-nosimd.a</Destination>
       </_MonoRuntimeArtifacts>
-      <_MonoRuntimeArtifacts Condition="('$(TargetsBrowser)' == 'true'  or '$(TargetsWasi)' == 'true') and '$(BuildMonoAOTCrossCompilerOnly)' != 'true'" Include="$(MonoObjDir)_deps\fetchzlibng-build\libz.a">
-        <Destination>$(RuntimeBinDir)libz.a</Destination>
-      </_MonoRuntimeArtifacts>
     </ItemGroup>
 
     <Copy SourceFiles="@(_MonoRuntimeArtifacts)"
diff --git a/src/mono/wasi/runtime/CMakeLists.txt b/src/mono/wasi/runtime/CMakeLists.txt
index ff92bae2d7011b..38928bf19fbfb1 100644
--- a/src/mono/wasi/runtime/CMakeLists.txt
+++ b/src/mono/wasi/runtime/CMakeLists.txt
@@ -27,11 +27,11 @@ target_link_libraries(dotnet
     ${MONO_ARTIFACTS_DIR}/libmonosgen-2.0.a
     ${MONO_ARTIFACTS_DIR}/libmono-icall-table.a
     ${MONO_ARTIFACTS_DIR}/libmono-wasm-${CONFIGURATION_INTERPSIMDTABLES_LIB}.a
-    ${MONO_ARTIFACTS_DIR}/libz.a
     ${NATIVE_BIN_DIR}/wasm-bundled-timezones.a
     ${NATIVE_BIN_DIR}/libSystem.Native.a
     ${NATIVE_BIN_DIR}/libSystem.Globalization.Native.a
     ${NATIVE_BIN_DIR}/libSystem.IO.Compression.Native.a
+    ${NATIVE_BIN_DIR}/libz.a
 )
 
 set_target_properties(dotnet PROPERTIES
diff --git a/src/native/external/zlib-ng.cmake b/src/native/external/zlib-ng.cmake
index c77f8e214a0ab6..ed86660ea70e81 100644
--- a/src/native/external/zlib-ng.cmake
+++ b/src/native/external/zlib-ng.cmake
@@ -1,4 +1,4 @@
- # IMPORTANT: do not use add_compile_options(), add_definitions() or similar functions here since it will leak to the including projects 
+ # IMPORTANT: do not use add_compile_options(), add_definitions() or similar functions here since it will leak to the including projects
 
 include(FetchContent)
 
@@ -16,9 +16,15 @@ set(WITH_RVV OFF)
 # We don't support ARMv6 and the check works incorrectly when compiling for ARMv7 w/ Thumb instruction set
 set(WITH_ARMV6 OFF)
 
-# 'aligned_alloc' is not available in browser/wasi, yet it is set by zlib-ng/CMakeLists.txt.
 if (CLR_CMAKE_TARGET_BROWSER OR CLR_CMAKE_TARGET_WASI)
+  # 'aligned_alloc' is not available in browser/wasi, yet it is set by zlib-ng/CMakeLists.txt.
   set(HAVE_ALIGNED_ALLOC FALSE CACHE BOOL "have aligned_alloc" FORCE)
+
+  # zlib-ng uses atomics, so we need to enable threads when requested for browser/wasi, otherwise the wasm target won't have thread support.
+  if (CMAKE_USE_PTHREADS)
+      add_compile_options(-pthread)
+      add_linker_flag(-pthread)
+  endif()
 endif()
 
 set(BUILD_SHARED_LIBS OFF) # Shared libraries aren't supported in wasm
diff --git a/src/native/libs/System.IO.Compression.Native/CMakeLists.txt b/src/native/libs/System.IO.Compression.Native/CMakeLists.txt
index e13e1271809b17..ebd23bb947e4d6 100644
--- a/src/native/libs/System.IO.Compression.Native/CMakeLists.txt
+++ b/src/native/libs/System.IO.Compression.Native/CMakeLists.txt
@@ -91,6 +91,10 @@ if (CLR_CMAKE_TARGET_UNIX OR CLR_CMAKE_TARGET_BROWSER OR CLR_CMAKE_TARGET_WASI)
     endif()
 
     set_target_properties(System.IO.Compression.Native-Static PROPERTIES OUTPUT_NAME System.IO.Compression.Native CLEAN_DIRECT_OUTPUT 1)
+
+    if (NOT CLR_CMAKE_USE_SYSTEM_ZLIB)
+        install (TARGETS zlib DESTINATION ${STATIC_LIB_DESTINATION} COMPONENT libs)
+    endif()
 else ()
     if (GEN_SHARED_LIB)
         include (GenerateExportHeader)
@@ -163,12 +167,11 @@ else ()
     if(STATIC_LIBS_ONLY)
         install_static_library(System.IO.Compression.Native.Aot aotsdk nativeaot)
         install_static_library(System.IO.Compression.Native.Aot.GuardCF aotsdk nativeaot)
+        if (NOT CLR_CMAKE_USE_SYSTEM_ZLIB)
+            install_static_library(zlib aotsdk nativeaot)
+        endif()
     endif()
 
 endif ()
 
-if((NOT CLR_CMAKE_USE_SYSTEM_ZLIB) AND STATIC_LIBS_ONLY)
-    install_static_library(zlib aotsdk nativeaot)
-endif()
-
 install (TARGETS System.IO.Compression.Native-Static DESTINATION ${STATIC_LIB_DESTINATION} COMPONENT libs)