The 29-year-old has been heavily linked with a move to The Emirates in recent days as Unai Emery searches for his first signings as Gunners boss.
The Daily Mirror is now reporting that the central defender is set to sign a three year contract with the Gunners to become their first summer signing, with the option for a further year.
It is claimed that Manchester United were also keeping tabs on the defender recently but he has opted against a move to Old Trafford and is instead getting ready to sign for their Premier League rivals Arsenal. The transfer fee is believed to be in the region of £16m.
Manchester United reportedly scouted Papastathopoulos as they searched for a partner for Eric Bailly in the heart of their defence.
However, the defender’s father Charalambos has now claimed that his son turned down the prospect of a move to Manchester United and the chance to work under Jose Mourinho.
He told Greek radio station Radio 24/7, as quoted in the same Daily Mirror article: “There was interest from United but he had to wait until July for them.
“United have a very good relationship with Dortmund, the teams talked but Sokratis chose to go to Arsenal.
“Arsenal had talked two years ago but I don’t know why he didn’t sign.
“He is going to a higher level, the world’s most competitive league and I believe he will do very well.”
Arsenal finished sixth in the Premier League table last season as they missed out on Champions League qualification for the second campaign running.
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