The 26-year-old Holland keeper is believed to be United’s number one target to replace David De Gea if the Spain stopper heads off, as expected, to Real Madrid.

United have been linked with Tottenham’s Hugo Lloris and Atletico Madrid’s Jan Oblak but goalkeeping coach Frans Hoek has prioritised a move for Cillessen, who featured in the Holland World Cup squad under Louis van Gaal.

However, Cillessen reckons Ajax will do everything in their power to stop him moving to Old Trafford.

“The Ajax management are going to make it really difficult when the interest becomes concrete,” Cillessen told the Sunday Mirror.

“If I had planned to leave, I would not have signed a new contract until 2018. My old contract was expiring in the summer of 2016 and in that case this summer would have been the perfect moment to leave.

“[Ajax coach] Frank de Boer has been very clear when he received questions about my transfer – he wants to block it.”

German giants Bayern Munich are also now believed to be tracking Cillessen, who would command a fee close to £20million.

Cillessen added: “Since the World Cup in Brazil the whole world has changed for me. It says something about my status that I am now linked to such big clubs.

“I can’t walk in public anymore. I can’t sit in a restaurant without being asked for photos and autographs.”