It comes following weeks of speculation that saw north London rivals Tottenham attempt to hijack the move at one point. He will sign a five-year deal and will spend the coming season back on loan with Saint-Etienne.
Arsenal have already signed 18-year-old Brazilian forward Gabriel Martinelli and are chasing deals for, Wilfried Zaha, Everton Soares and Kieran Tierney.
Saliba will be the first signing to be completed under new technical director Edu, who was brought in by the club to oversee all first-team action, including the recruitment of new players.
And while Nicholas does highlight the jump in class he also believes that the 22-year-old will be a vast improvement on what Arsenal already have.
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That showed in one last slash out of the rough in the rain on 18, then a putt from off the green that got only halfway there. I'm proud of myself to reset and get the attitude right after [Thursday's triple-bogey finish]".
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European Commission President Ursula von der Leyen said she would extend the negotiation term for Brexit if London gives a good reason for that, Reuters reported.
Celtic manager Neil Lennon has reportedly admitted that his star left-back Kieran Tierney is similar to former Manchester United superstar Cristiano Ronaldo and stated that he would like to keep hold of the Scotsman despite the fact that Arsenal is interested in his signature.
His arrival suggests the Scottish champions are preparing for life after Tierney with Arsenal's interest still strong.
But the deal did not seem to make any progress and Sky Sports have been claiming that the Bhoys are not happy with the offer since they want more cash upfront in exchange of Kieran Tierney.
Earlier, Arsenal captain and French defender Laurent Koscielny gave manager Unai Emery a bit of trouble in the pre-season, by refusing to train with his teammates in the U.S. before the 2019-20 campaign.
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