Arsenal will this week tie up the signing of the Marseille and France midfielder Franck Ribéry in a deal that is expected to cost the Gunners a minimum £13.5m.

Although sources close to the player insisted yesterday that nothing has been finalised, his agent Bruno Heiderscheid declared on Sunday that "a transfer offer for Franck" would be "registered with [Marseille's chairman] Pape Diouf within 24 or 48 hours." That offer is from Arsenal and this morning's edition of France Football, a publication close to Wenger, confirms the move.

The arrival at the Emirates Stadium of the France international, who emerged as his nation's most exciting prospect in their run to the World Cup final, will finally see Arsenal's manager Arsène Wenger relent over Ashley Cole's future and authorise his £25m departure to the Premiership champions Chelsea.

"I do not know what will happen with Ashley Cole in the next few days," Wenger said yesterday, "but for me, certainly, the deadline has come now to make a decision one way or the other. This week is the last limit I can expect something to happen. To play the football I love, I need the players who can play the game I love and until now we always managed to do that.

"We have one advantage in that we've never been a prisoner of names. There are many people who have predicted many times that we'll collapse and we've always improved. I have in my squad good enough players no matter who leaves."

But even that may not end Arsenal's summer transfer business. Ribéry's arrival will harden the resolve of Real Madrid to recruit José Antonio Reyes from Arsenal. The Gunners also retain a strong interest in Chelsea's William Gallas.

Madrid had also pursued Ribéry, with the failed presidential candidate Juán Miguel Villar Mir having made a verbal £26m bid to Marseille in the run-up to elections. However, the tycoon's defeat by Juán Ramón Calderón in the Bernabéu ballot led to the withdrawal of that offer. The Spanish club's subsequent interest, reactivated last week, produced a much-reduced offer.

The two clubs may now go head to head once more for the services of Gallas, whose agent was in London yesterday to talk through his situation with the Chelsea board. Seen by Arsenal as the perfect replacement for Sol Campbell and wanted by Real as Fabio Cannavaro's foil, Gallas's future at Stamford Bridge is unclear after he refused to join the Premiership champions on their United States tour.

Arsenal will find it considerably harder to compete with Madrid for Gallas, however. Though the Gunners held the aces in the Ribéry stakes, Chelsea would sooner sell the defender to the Spanish club than to a bitter Premiership rival.

Ribéry believes that joining Wenger is the best move for his career. He has taken soundings from several sources, among them his France team mate and Arsenal's captain Thierry Henry. Most influential, though, was Marseille's former sporting director Henri Bianchéri, who shared a spell at Monaco with Wenger and offered a glowing appraisal of the Highbury manager.

Wenger hopes that Ribéry will now settle in north London and spend a lengthy spell maturing at the club's new stadium. As a youngster the midfielder slipped through the net of the French scouting system, beginning his senior career with his home-town club of Boulogne-sur-Mer, an amateur team, five years ago. Since then he has played at five other clubs, including a six-month spell at Galatasaray, all of which ensured that Ribéry has never received the sustained level of coaching his raw talents undoubtedly deserve.

His technical ability to carry the ball at speed was on display at the World Cup. Ribery, who only made his international debut in France's narrow tournament-warm-up win against Mexico on May 27, was a surprise inclusion in the squad for Germany. The national team manager Raymond Domenech referred to the selection of the player as his "joker".

Ribéry rewarded that faith with the first goal in France's crucial second-round win against Spain, his pace taking him past the goalkeeper Iker Casillas and providing him an empty net in which to score.

English scouts - Manchester United were the first to make a £9m offer to Marseille shortly before the tournament began - would have recognised this talent from his almost singlehanded destruction of the England Under-21 team last November, when the midfielder's pace proved unmanageable for a strong team of English counterparts.

The departure of the England left-back Cole is likely now to be finalised before the week is out. The defender was left out of the squad that travelled to Zagreb for tonight's Champions League qualifier and could sign for Chelsea in time for Sunday's Community Shield.