The top US commander in Afghanistan has criticised a Florida church's plan to burn copies of the Koran on the anniversary of the September 11 terrorist attacks.

The Dove World Outreach Centre says it will burn the Muslim holy book as a warning against what it calls the "threat posed by Islam".

But General David Petraeus say the demonstration could cause significant problems for American troops overseas.

"It could endanger troops and it could endanger the overall effort," he said in a statement.

"It is precisely the kind of action the Taliban uses and could cause significant problems. Not just here, but everywhere in the world, we are engaged with the Islamic community."

Army spokesman Lieutenant General William Caldwell says the plan has already caused a lot of anger in the region.

"It has amongst the Afghan people - that's correct," he said.

"It's their holy book, and so when somebody says that they're going to destroy that and cause a desecration to something that's very sacred to them, it's already stirred up a lot of discussion and concern amongst the people," he said.