Ilkay Gundogan 'can leave Barcelona before the end of the transfer window' if they fail to register him in time

Ilkay Gundogan's move to Barcelona was announced on Monday but he could leave the club for free in just two months time.

There has been speculation for weeks about Gundogan's future, even before he helped Manchester City win the Champions League, Premier League and FA Cup.

With his contract expiring it became more expected that he would leave the Etihad Stadium, despite Pep Guardiola wanting to keep him.

Arsenal were desperate to lure him to the Emirates but it always looked like he would be heading to La Liga to join the Spanish champions.

Gundogan has signed a two year deal at the Nou Camp with the option for a third year, although he won't get to play at the famous stadium in his debut campaign with renovations continuing.

More news about the move has started to be revealed following Monday's announcement, including the fact he became the club's priority once they missed out on Lionel Messi.

One reason they seem to have not re-signed the seven time Ballon d'Or winner is worries about their finances, the reason they lost him in the first place.

In recent years the club have struggled to register their new signings, often waiting weeks and having to sell players before they could do so.

And according to The Athletic, Gundogan has a built in clause in his contract that allows him to leave for free if he can't be registered by the end of the transfer window.

On top of that he will be paid the entirety of his first year salary, which will be just over €9 million after tax.

The report explains that City believed the German would have signed to stay with them had they offered more than one year guaranteed.

Interestingly the 32-year-old was also offered more money than both Barcelona and City put on the table in order to move to Saudi Arabia.

The Saudi Pro League is being led by the country's Public Investment Fund after they took over the four biggest clubs in the league.

They have already signed several high profile players this summer and former Liverpool striker Roberto Firmino could be the next star arriving.