The speculation increased when the 24-year-old waved to United fans as he left the pitch at Old Trafford last week after suffering an injury in the 1-1 draw against Arsenal, but Van Gaal said that should not be taken as a sign he is set to leave.
De Gea is a doubt for the clash against Hull but Van Gaal feels his long term future is secure.
“I believe still that David de Gea shall stay. He has trained today but only with our goalkeeper trainer. He still has a little problem so I want to wait a day longer because I want him to play against Hull City.
“You know that I shall talk with them maybe tomorrow, we’ll have a farewell drink. After the match, I have the Monday to talk, I have spoken to some players this week. You have to wait and see how these talks develop in terms of players staying or going away.”
Victor Valdes made his Manchester United debut against Arsenal, 130 days after signing for the club. Van Gaal believes he is ready to step in, but won’t look past keeping De Gea.
“He is of course good enough to be a Manchester United goalkeeper otherwise he wouldn’t be here. First we have to wait and see if De Gea is leaving and after that we shall talk about the other things.”
Van Gaal went on to confirm Wayne Rooney is fit to return following a dead leg suffered in the win against Crystal Palace.
“Rooney is available,” he added. “He is captain, so he shall play.
The Dutchman also insisted his team would be fully motivated against Hull – who need to beat United to have any chance of Premier League survival.
“We have the same approach as ever,” he said. “We have to give our utmost best. We have to do that for the honesty of the league. I have to play my strongest team.”