The West Brom goalkeeper is likely to be confirmed as one of two back-up options to No 1 Joe Hart when Roy Hodgson names his provisional squad on Monday.
And Foster told Sky Sports News' Weekend Warm-up programme he will be happy just to play second fiddle to Hart in Brazil.
"I think Joe Hart should be No 1," he said. "God forbid he gets injured - he is a fantastic goalkeeper and we are lucky to have someone like him.
"I get to see him close up in training and he is brilliant, fantastic. I don't think there are any worries on that front.
"For me it is going to be a real honour to be involved in a World Cup squad - I have never been involved in a major tournament. If I get the call I am really going to be looking forward to it."
Foster's chances of representing England in a World Cup tournament appeared dead and buried when he retired from international football during the Fabio Capello era.
He reversed that decision a year ago and was welcomed back by Hodgson, his former manager at West Brom.
He said: "At the time I was going through a lot of injuries - knee trouble, back trouble. I'd just had kids as well, so to be away from home for two weeks at a time was a big miss for me.
"It was something I needed to do and something I stand by even today."