diff --git a/lib/libutee/include/tee_arith_internal.h b/lib/libutee/include/tee_arith_internal.h
index fc5678edc20..cf1d3edd7e1 100644
--- a/lib/libutee/include/tee_arith_internal.h
+++ b/lib/libutee/include/tee_arith_internal.h
@@ -22,12 +22,6 @@
  */
 #define TEE_MATHAPI_EXPORT
 
-/*
- * The modes for String Conversion
- */
-#define TEE_STRING_MODE_HEX_UC MPA_STRING_MODE_HEX_UC
-#define TEE_STRING_MODE_HEX_LC MPA_STRING_MODE_HEX_UC
-
 /*------------------------------------------------------------
  *
  *  Define IN, OUT, INBUF and OUTBUF to keep format from the spec.
diff --git a/mk/config.mk b/mk/config.mk
index 28ae093f40a..8896165256f 100644
--- a/mk/config.mk
+++ b/mk/config.mk
@@ -705,6 +705,11 @@ CFG_TA_BIGNUM_MAX_BITS ?= 2048
 # Set this to a lower value to reduce the memory footprint.
 CFG_CORE_BIGNUM_MAX_BITS ?= 4096
 
+# Not used since libmpa was removed. Force the values to catch build scripts
+# that would set = n.
+$(call force,CFG_TA_MBEDTLS_MPI,y)
+$(call force,CFG_TA_MBEDTLS,y)
+
 # Compile the TA library mbedTLS with self test functions, the functions
 # need to be called to test anything
 CFG_TA_MBEDTLS_SELF_TEST ?= y
diff --git a/ta/ta.mk b/ta/ta.mk
index e09792e2e86..09c20bfa16f 100644
--- a/ta/ta.mk
+++ b/ta/ta.mk
@@ -33,6 +33,7 @@ ta-mk-file-export-vars-$(sm) += CFG_CACHE_API
 ta-mk-file-export-vars-$(sm) += CFG_SECURE_DATA_PATH
 ta-mk-file-export-vars-$(sm) += CFG_TA_MBEDTLS_SELF_TEST
 ta-mk-file-export-vars-$(sm) += CFG_TA_MBEDTLS
+ta-mk-file-export-vars-$(sm) += CFG_TA_MBEDTLS_MPI
 ta-mk-file-export-vars-$(sm) += CFG_SYSTEM_PTA
 ta-mk-file-export-vars-$(sm) += CFG_FTRACE_SUPPORT
 ta-mk-file-export-vars-$(sm) += CFG_UNWIND