Peters, who scored England's second goal in their 4-2 win over West Germany in the 1966 final, was concerned by the defence and believed that if opponents stifle striker Wayne Rooney, England could struggle.
"I think it will be difficult. There's a few problems... especially in defence. We certainly haven't got a (goalkeeper like) Gordon Banks," he told the Independent on Sunday.
"I think Robert Green will take over from David James in goal.
"Glen Johnson at right-back has been injured and is more of an attacking player than a defensive one, and of course there's Ashley Cole's broken ankle and a problem with Wayne Bridge. Rio Ferdinand's got a bit of a back problem.
"So it looks a bit iffy. Then, no disrespect to Emile Heskey, but he's played 50-odd games for England and scored seven goals.
"Although he works his socks off... if you're a centre-forward you need to score a few goals, don't you ?"
He also said that Rooney's influence could be diminished by the opposition but added that coach Fabio Capello reminded him of England's World Cup winning manager Alf Ramsey.
"He (Capello) reminds me of Alf the way he goes about his business," Peters said. "You don't mess around with him.
"He seems to approach the whole job better than the last four or five people and the respect the players seem to have for him is outstanding. Nobody will take a liberty, that's for sure."
England face the United States, Algeria and Slovenia in Group C when the event kicks off on June 11.
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