Arsène Wenger has confirmed Jack Wilshere will miss England's friendlies against Republic of Ireland and Brazil to undergo a minor operation on his right ankle.

The Arsenal midfielder had a pin inserted in the joint during 2011 to help cure a stress fracture he had sustained during that summer and which kept him out of action for 15 months. Wilshere returned to Arsenal's first team last October, in the 1-0 home victory over Queens Park Rangers, but has remained dogged by the injury and will undergo a second procedure following his side's final game of the season, against Newcastle on Sunday.

Wenger expects the 21-year-old to be fit for Arsenal's pre-season tour of south-east Asia and Japan, which begins with a match against an Indonesia XI in Jakarta on 14 July, but said there is no chance of him playing in England's fixtures with Ireland at Wembley on 29 May and Brazil at the Maracanã four days later.

"He will have small surgery after the season," said Wenger, who recently admitted to rushing Wilshere back from injury after he hurt his other ankle in the defeat by Tottenham on 3 March. "At the moment he plays with painkillers and I use him only when it's really needed. It [the operation] is a very small one – a two- to three-week job to take out a pin. It will not be a problem."

Wilshere's absence is a blow for Roy Hodgson, who has been able to call on the midfielder only twice since becoming England manager just over a year ago. Hodgson deems Wilshere to be a key part of the team's precarious attempts to qualify for the 2012 World Cup in Brazil. They sit second in Group H, two points behind Montenegro with four games left.

Asked if Wilshere is disappointed at having to miss out on playing for his country in the coming weeks, and in particular against Brazil, Wenger replied somewhat mischievously: "Of course, but he will go next year."

Arsenal face Wigan at the Emirates on Tuesday in a match of huge importance for both clubs. They must win if they are to overtake Tottenham in fourth place ahead of the weekend's final Premier League fixtures, with anything less putting their 100% record of qualifying for the Champions League under Wenger in jeopardy.

Wigan will be all but relegated should they fail to secure three points, creating history by becoming the first team to win the FA Cup and lose their top-flight status in the same season.

"Both teams are in the same situation so that means they will play absolutely 100%," Wenger said. "We have to be at our best. The players have experience, a good solid attitude, a good strong spirit, so the ingredients are there to do it."

Wenger, who has a full squad to chose from, is concerned that Arsenal have not played since their victory at QPR on 4 May but feels their form – they are unbeaten in their past nine matches – should make up for any rustiness.

He also expressed reservations about Wigan's ability to avoid relegation, describing it as a concern that, yet again, Roberto Martínez's men find themselves in an end-of-season fight for top-flight survival.

"Wigan are a bit repeated every year," he said. "They get out every time, just, but when you play with fire all the time it can be dangerous."

That is not a view shared by the ever-confident Martínez, who believes his team can win their final two games of the season – after Tuesday they host fellow relegation candidates Aston Villa on Sunday – and has insisted that winning the club's first major trophy by beating Manchester City in the FA Cup final will not distract his players.

"It will be impossible for us to forget the emotions we had on Saturday," said Martínez, who is hoping to have Jean Beausejour back from injury.

"Winning this trophy is very special and takes the club into a different richness in terms of our tradition. It was a moment that changed the perception of our club for millions of people and that is really positive. But it does not need to affect the next two matches – if we win the six points we don't have to rely on anyone."