Checking environment variables value in Makefile WIndows

Question

I want to check if my environment variable is set, but this doesn't work.

!IFDEF VAL
    echo %VAL%
!ELSE
    echo "NOT SET"
!ENDIF

I know that on linux you can use ifeq, but there is no such thing in the windows makefile. Please help.

Edit: I use nmake from cl2022 in cmd.