The Brazilian was named in the 23-man squad for next month’s Russia finals by coach Tite.
The 25-year-old Shakhtar Donetsk midfielder has long been linked with a move to Old Trafford, but has insisted he will only make a decision after the finals.
Fred has been highly coveted by a number of top European club and it is understood United are among those interested in signing him.
He was expected to sign for Manchester City in January but Pep Guardiola turned his attention instead to concluding a deal for central defender Aymeric Laporte, who arrived from Athletic Bilbao for a club record £57m.
It is understood their interest has cooled but United still face competition from a number of clubs for Fred’s signature, including PSG.
Now the Brazilian has admitted he will ‘look at his options’ after the World Cup and has told how he dreams of playing for major clubs in Europe.
Speaking to SporTV, he said: “I’m very happy at Shakhtar. I’ve been working well here but it has been five years.
“I made it clear to the club that I was very happy here but I want to make a bigger leap in my career. There are other clubs interested in England and France. I want to make a bigger leap, I made it clear to the club.
“Now I just have to wait to get through the World Cup and see which is the best destination. I think I have to change a little. I have dreams of playing in major clubs in Europe. I made it clear that it’s my moment.
“The club are reluctant to release (me). I have a contract until 2021. As soon as I come back from the World Cup we will sit down, talk and look at the options.”
The MEN wrote in March that United manager Jose Mourinho is keen on making two central midfield additions amid the possible departure of Marouane Fellaini, as well as the retirement of Michael Carrick.
Mourinho hinted last month he could make a Brazilian signing amid interest in Juventus left-back Alex Sandro and Chelsea winger Willian. Fred has only attained seven Brazil caps but was called up for their World Cup warm-up matches against Russia and Germany in March.
Fred played against David Moyes’s United in their Champions League group stage defeat at Old Trafford in December 2013, having joined Shakhtar earlier that year. Fred served a worldwide doping ban after he tested positive for the banned substance hydrochlorothiazide at the 2015 Copa America.