A top US veterans group on Tuesday blasted a planned Koran burning to mark nine years since the September 11th strikes as the work of "religious extremists" whose gesture would endanger US forces.

"There is nothing to be gained and everything to lose from this selfish act," said Richard Eubank, leader of the Veterans of Foreign Wars (VFW), the largest US combat veterans organization with 1.5 million members.

"Our war is against a small number of religious extremists who kill indiscriminately and without remorse. Let's not allow an equally small number of religious extremists in America to widen the war," said Eubank.

Eubank deplored that the action, planned for Saturday by a Florida Christian evangelical church, risked outweighing years of US actions that he described as having built up goodwill among Muslims toward the United States.

"No one will remember the tremendous multi-national coalition that freed Kuwait back in 1991, or America's huge humanitarian response in Indonesia after the 2005 tsunami or this year's disastrous flooding in Pakistan," he said.

"The only thing Muslims will remember and our enemies will exploit was American laws permitted American citizens to burn the Islamic holy book without consequence," he said.

The VFW stressed in a statement at that the "self-serving" move would "fuel anti-American sentiment for years" and further endanger US forces in places like Afghanistan.

Saturday's anniversary of the September 11, 2001 attacks in which the World Trade Center was destroyed is also set to coincide with the festivities for the Eid al-Fitr, marking the end of the Islamic fasting month of Ramadan.

A small Florida church has vowed to mark Saturday's anniversary and remember the deaths of almost 3,000 people killed in the Al-Qaeda attack by burning a Koran.

Pastor Terry Jones said the Koran torching aimed "to remember those who were brutally murdered on September 11," and to send a warning "to the radical element of Islam."