Raheem Sterling will reportedly not open negotiations with Manchester City over a new contract until after the upcoming World Cup this summer.
The England forward has hit the ground running this season, scoring 13 goals in 20 games across all competitions, including crucial late winners against Bournemouth, Huddersfield and Southampton.
Sterling has two years left on the £180,000-a-week deal he signed when he joined from Liverpool for £49m in the summer of 2015 and City were thought to be keen to tie him down to a new contract.
However, according to the Mirror, Sterling, who turns 23 on Friday (8 December), wants to put contract talks on hold to focus on helping City to win the title and on maintaining his form ahead of the World Cup.
Real Madrid are understood to be monitoring the situation after they were linked with the England international two years ago and their interest could be revived, should contract negotiations fail to progress as expected.
Earlier this season, Guardiola ruled out the possibility of selling Sterling, stating there was "no chance" the forward would be allowed to leave the Etihad Stadium.
In the final days of the summer transfer window, reports suggested that City had made a desperate attempt to bring Alexis Sanchez to the club by offering Sterling in a cash-plus-player deal. Guardiola later claimed that it was actually Arsenal who had submitted the proposal, one which was emphatically rejected by the two-time Premier League champions.
"Raz [Raheem] is staying here," Guardiola told the London Evening Standard in September. "The club trust him, that is why we have invested a lot of money in him, so the players we have are going to stay.
"If they want to leave they are going to leave, but he wants to stay. If players want to leave they have to ask the chairman, but there is no chance of that. He is going nowhere."