diff --git a/pgpy/packet/packets.py b/pgpy/packet/packets.py
index cd494137..9baf0774 100644
--- a/pgpy/packet/packets.py
+++ b/pgpy/packet/packets.py
@@ -255,7 +255,7 @@ def encrypt_sk(self, pk, symalg, symkey):
         m = bytearray(self.int_to_bytes(symalg) + symkey)
         m += self.int_to_bytes(sum(bytearray(symkey)) % 65536, 2)
 
-        if self.pkalg == PubKeyAlgorithm.RSAEncryptOrSign:
+        if self.pkalg == PubKeyAlgorithm.RSAEncryptOrSign or self.pkalg == PubKeyAlgorithm.RSAEncrypt:
             encrypter = pk.keymaterial.__pubkey__().encrypt
             encargs = (bytes(m), padding.PKCS1v15(),)