diff --git a/library/pkwrite.c b/library/pkwrite.c
index e00545881..cb3c426f6 100644
--- a/library/pkwrite.c
+++ b/library/pkwrite.c
@@ -66,9 +66,27 @@ static int pk_write_rsa_pubkey( unsigned char **p, unsigned char *start,
 {
     int ret;
     size_t len = 0;
+    mbedtls_mpi T;
 
-    MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_mpi( p, start, &rsa->E ) );
-    MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_mpi( p, start, &rsa->N ) );
+    mbedtls_mpi_init( &T );
+
+    /* Export E */
+    if ( ( ret = mbedtls_rsa_export( rsa, NULL, NULL, NULL, NULL, &T ) ) != 0 ||
+         ( ret = mbedtls_asn1_write_mpi( p, start, &T ) ) < 0 )
+        goto end_of_export;
+    len += ret;
+
+    /* Export N */
+    if ( ( ret = mbedtls_rsa_export( rsa, &T, NULL, NULL, NULL, NULL ) ) != 0 ||
+         ( ret = mbedtls_asn1_write_mpi( p, start, &T ) ) < 0 )
+        goto end_of_export;
+    len += ret;
+
+end_of_export:
+
+    mbedtls_mpi_free( &T );
+    if( ret < 0 )
+        return( ret );
 
     MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) );
     MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_CONSTRUCTED |
@@ -205,18 +223,70 @@ int mbedtls_pk_write_key_der( mbedtls_pk_context *key, unsigned char *buf, size_
 #if defined(MBEDTLS_RSA_C)
     if( mbedtls_pk_get_type( key ) == MBEDTLS_PK_RSA )
     {
+        mbedtls_mpi T; /* Temporary holding the exported parameters */
         mbedtls_rsa_context *rsa = mbedtls_pk_rsa( *key );
 
-        MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_mpi( &c, buf, &rsa->QP ) );
-        MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_mpi( &c, buf, &rsa->DQ ) );
-        MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_mpi( &c, buf, &rsa->DP ) );
-        MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_mpi( &c, buf, &rsa->Q ) );
-        MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_mpi( &c, buf, &rsa->P ) );
-        MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_mpi( &c, buf, &rsa->D ) );
-        MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_mpi( &c, buf, &rsa->E ) );
-        MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_mpi( &c, buf, &rsa->N ) );
-        MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_int( &c, buf, 0 ) );
+        /*
+         * Export the parameters one after another to avoid simultaneous copies.
+         */
 
+        mbedtls_mpi_init( &T );
+
+        /* Export QP */
+        if( ( ret = mbedtls_rsa_export_crt( rsa, NULL, NULL, &T ) ) != 0 ||
+            ( ret = mbedtls_asn1_write_mpi( &c, buf, &T ) ) < 0 )
+            goto end_of_export;
+        len += ret;
+
+        /* Export DQ */
+        if( ( ret = mbedtls_rsa_export_crt( rsa, NULL, &T, NULL ) ) != 0 ||
+            ( ret = mbedtls_asn1_write_mpi( &c, buf, &T ) ) < 0 )
+            goto end_of_export;
+        len += ret;
+
+        /* Export DP */
+        if( ( ret = mbedtls_rsa_export_crt( rsa, &T, NULL, NULL ) ) != 0 ||
+            ( ret = mbedtls_asn1_write_mpi( &c, buf, &T ) ) < 0 )
+            goto end_of_export;
+        len += ret;
+
+        /* Export Q */
+        if ( ( ret = mbedtls_rsa_export( rsa, NULL, NULL, &T, NULL, NULL ) ) != 0 ||
+             ( ret = mbedtls_asn1_write_mpi( &c, buf, &T ) ) < 0 )
+            goto end_of_export;
+        len += ret;
+
+        /* Export P */
+        if ( ( ret = mbedtls_rsa_export( rsa, NULL, &T, NULL, NULL, NULL ) ) != 0 ||
+             ( ret = mbedtls_asn1_write_mpi( &c, buf, &T ) ) < 0 )
+            goto end_of_export;
+        len += ret;
+
+        /* Export D */
+        if ( ( ret = mbedtls_rsa_export( rsa, NULL, NULL, NULL, &T, NULL ) ) != 0 ||
+             ( ret = mbedtls_asn1_write_mpi( &c, buf, &T ) ) < 0 )
+            goto end_of_export;
+        len += ret;
+
+        /* Export E */
+        if ( ( ret = mbedtls_rsa_export( rsa, NULL, NULL, NULL, NULL, &T ) ) != 0 ||
+             ( ret = mbedtls_asn1_write_mpi( &c, buf, &T ) ) < 0 )
+            goto end_of_export;
+        len += ret;
+
+        /* Export N */
+        if ( ( ret = mbedtls_rsa_export( rsa, &T, NULL, NULL, NULL, NULL ) ) != 0 ||
+             ( ret = mbedtls_asn1_write_mpi( &c, buf, &T ) ) < 0 )
+            goto end_of_export;
+        len += ret;
+
+    end_of_export:
+
+        mbedtls_mpi_free( &T );
+        if( ret < 0 )
+            return( ret );
+
+        MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_int( &c, buf, 0 ) );
         MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, buf, len ) );
         MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, buf, MBEDTLS_ASN1_CONSTRUCTED |
                                                     MBEDTLS_ASN1_SEQUENCE ) );