Sanchez addressed Spains players on Tuesday ahead of their campaign in Russia, but while he was given a round of applause by the squad after he had finished speaking De Gea was stood still with his hands in his pockets.
The tension between De Gea and Sanchez can be traced back to 2016 when the Manchester United goalkeeper was wrongly implicated in a sexual assault investigation in Spain.
Shortly before the start of Euro 2016, De Gea was accused of setting up a meeting between two women and two Spain Under-21 players which led to a sexual assault at a hotel in Madrid.
De Gea denied all allegations and was subsequently cleared of any wrongdoing after the investigation collapsed due to a lack of evidence.
But shortly after De Gea had been named in the case, Pedro Sanchez, who was sworn in as Spains new prime minister by King Felipe last week, said in an interview with El Diario that he did not want the 27-year-old representing the national team.
I dont feel comfortable seeing De Gea in goal for Spain right now, he said.
Of course, there is innocence until guilt is proven but I put myself on the side of the victim.
De Gea is currently preparing with the rest of Spains squad for the World Cup in Russia.
Julen Lopeteguis side are in Group B and will begin their tournament against Portugal on June 15 before facing Iran and then Morocco.
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