diff --git a/icu4c/source/data/makedata.mak b/icu4c/source/data/makedata.mak
index e8a33ff85dd..95d6baff562 100644
--- a/icu4c/source/data/makedata.mak
+++ b/icu4c/source/data/makedata.mak
@@ -142,13 +142,20 @@ TESTDATABLD=$(ICUP)\source\test\testdata\out\build
 ICUTOOLS=$(ICUP)\source\tools
 !MESSAGE ICU tools path is $(ICUTOOLS)
 
+NATIVE_ARM=
+!IF "$(PROCESSOR_ARCHITECTURE)" == "ARM64" || "$(PROCESSOR_ARCHITEW6432)" == "ARM64"
+NATIVE_ARM=ARM64
+!ELSE IF "$(PROCESSOR_ARCHITECTURE)" == "ARM" || "$(PROCESSOR_ARCHITEW6432)" == "ARM"
+NATIVE_ARM=ARM
+!ENDIF
+
 #   ARM_CROSS_BUILD
 #       In order to support cross-compiling for ARM/ARM64 using the x64 tools
 #       we need to know if we're building the ARM/ARM64 data DLL, otherwise
 #       the existence of the x64 bits will cause us to think we are already done.
 #    Note: This is only for the "regular" builds, the UWP builds have a separate project file entirely.
 ARM_CROSS_BUILD=
-!IF "$(UWP)" == ""
+!IF "$(UWP)" == "" && "$(NATIVE_ARM)" == ""
 !IF "$(CFG)" == "ARM\Release" || "$(CFG)" == "ARM\Debug"
 ARM_CROSS_BUILD=ARM
 ARM_CROSSBUILD_TS=$(ICUTMP)\$(ARM_CROSS_BUILD).timestamp
@@ -185,6 +192,18 @@ CFGTOOLS=x64\Debug
 !IF "$(CFG)" == "x86\Release" || "$(CFG)" == "x86\Debug"
 PATH = $(ICUP)\bin;$(PATH)
 ICUPBIN=$(ICUP)\bin
+# Use these path whether or not it's UWP build.
+!ELSE IF "$(NATIVE_ARM)" != ""
+!IF "$(CFG)" == "ARM\Release" || "$(CFG)" == "ARM\Debug"
+PATH = $(ICUP)\binARM;$(PATH)
+ICUPBIN=$(ICUP)\binARM
+!ELSE IF "$(CFG)" == "ARM64\Release" || "$(CFG)" == "ARM64\Debug"
+PATH = $(ICUP)\binARM64;$(PATH)
+ICUPBIN=$(ICUP)\binARM64
+!ELSE
+!ERROR Cross-build from ARM to x86 is not supported!
+!ENDIF
+# Build x86_64 or cross-build ARM
 !ELSE
 PATH = $(ICUP)\bin64;$(PATH)
 ICUPBIN=$(ICUP)\bin64
diff --git a/icu4c/source/extra/uconv/makedata.mak b/icu4c/source/extra/uconv/makedata.mak
index b30f59728b5..81fcc908ee6 100644
--- a/icu4c/source/extra/uconv/makedata.mak
+++ b/icu4c/source/extra/uconv/makedata.mak
@@ -51,8 +51,16 @@ PKGMODE=static
 ICD=$(ICUDATA)^\
 DATA_PATH=$(ICUP)\data^\
 
+NATIVE_ARM=
+!IF "$(PROCESSOR_ARCHITECTURE)" == "ARM64" || "$(PROCESSOR_ARCHITEW6432)" == "ARM64"
+NATIVE_ARM=ARM64
+!ELSE IF "$(PROCESSOR_ARCHITECTURE)" == "ARM" || "$(PROCESSOR_ARCHITEW6432)" == "ARM"
+NATIVE_ARM=ARM
+!ENDIF
+
 # Use the x64 tools for building ARM and ARM64.
 # Note: This is similar to the TOOLS CFG PATH in source\data\makedata.mak
+!IF "$(NATIVE_ARM)" == ""
 !IF "$(CFG)" == "x64\Release" || "$(CFG)" == "x64\Debug" || "$(CFG)" == "ARM\Release" || "$(CFG)" == "ARM\Debug" || "$(CFG)" == "ARM64\Release"  || "$(CFG)" == "ARM64\Debug"
 ICUTOOLS=$(ICUP)\bin64
 PATH = $(ICUP)\bin64;$(PATH)
@@ -60,6 +68,15 @@ PATH = $(ICUP)\bin64;$(PATH)
 ICUTOOLS=$(ICUP)\bin
 PATH = $(ICUP)\bin;$(PATH)
 !ENDIF
+!ELSE
+!IF "$(CFG)" == "ARM\Release" || "$(CFG)" == "ARM\Debug"
+ICUTOOLS=$(ICUP)\binARM
+PATH = $(ICUP)\binARM;$(PATH)
+!ELSE
+ICUTOOLS=$(ICUP)\binARM64
+PATH = $(ICUP)\binARM64;$(PATH)
+!ENDIF
+!ENDIF
 
 # If building ARM/ARM, then we need to pass the arch as an argument.
 EXTRA_PKGDATA_ARGUMENTS=