El Ahmadi has stated he is undergoing a medical at Villa Park.
Lambert said: "We're in talks at this moment, those talks are ongoing and we hope to reach a positive conclusion with Feyenoord and the player.
"Karim is a player who I feel could definitely improve our squad. He has experience of big club football and also at international level.
"He can pass the ball well and he could be an important player for us in central midfield.
"Let's see how things progress. We're very hopeful."