diff --git a/systemverilog-plugin/UhdmAst.cc b/systemverilog-plugin/UhdmAst.cc
index 6790fe9..73902f1 100644
--- a/systemverilog-plugin/UhdmAst.cc
+++ b/systemverilog-plugin/UhdmAst.cc
@@ -2709,14 +2709,26 @@
             current_node->type = AST::AST_REDUCE_XNOR;
             break;
         case vpiUnaryNandOp: {
-            current_node->type = AST::AST_REDUCE_AND;
-            auto not_node = new AST::AstNode(AST::AST_LOGIC_NOT, current_node);
+            auto not_node = new AST::AstNode(AST::AST_NONE, current_node);
+            if (current_node->children.size() == 2) {
+                current_node->type = AST::AST_BIT_AND;
+                not_node->type = AST::AST_BIT_NOT;
+            } else {
+                current_node->type = AST::AST_REDUCE_AND;
+                not_node->type = AST::AST_LOGIC_NOT;
+            }
             current_node = not_node;
             break;
         }
         case vpiUnaryNorOp: {
-            current_node->type = AST::AST_REDUCE_OR;
-            auto not_node = new AST::AstNode(AST::AST_LOGIC_NOT, current_node);
+            auto not_node = new AST::AstNode(AST::AST_NONE, current_node);
+            if (current_node->children.size() == 2) {
+                current_node->type = AST::AST_BIT_OR;
+                not_node->type = AST::AST_BIT_NOT;
+            } else {
+                current_node->type = AST::AST_REDUCE_OR;
+                not_node->type = AST::AST_LOGIC_NOT;
+            }
             current_node = not_node;
             break;
         }