The Holland international will see a second loan agreement with the Swans expire at the end of the season.
He has enjoyed a productive time at the Liberty Stadium, tasting League Cup success last term and netting seven goals so far in 2013/14.
De Guzman offered another timely reminder of his talents on Saturday as he bagged a brace in a vital 3-0 victory over Norwich City, and Monk admits tying up a permanent agreement for the Villarreal midfielder has become a top priority.
He said: "I would imagine he is a player who is at the top of our list, he is a very good player and he suits how we play.
"He was the man of the match, his movement and desire to get the ball back in an unfamiliar role were excellent and he was rewarded with two goals.
"He enjoys it here and he has thrived so he would be an important signing, but we have to speak to the player and see what he thinks."