UNITED NATIONS, May 30 (UPI) -- Recent accusations of gold-for-guns peacekeepers following a sex-for-food peacekeeping scandal in Congo have prompted a move for tighter troop discipline.

Troop-contributing countries must accept the introduction of formal discipline standards for peacekeepers or risk jeopardizing the United Nations' entire recent campaign of zero-tolerance to peacekeeping crimes, the top U.N. peacekeeper said Tuesday.

Undersecretary-General Jean-Marie Guehenno, head of the U.N. Department of Peacekeeping Operations, told reporters at U.N. World Headquarters in New York discipline in the field must be improved.

Discussions are about to resume with U.N. member states on a proposed memorandum of understanding setting out standards for the estimated 100,000 peacekeepers operating in 18 separate missions around the world, he said.

The standards, which would be contained in the MOU, are part of the U.N. Secretariat's response to a series of scandals in recent years over the behavior by some U.N. peacekeepers.

But Guehenno said some states have indicated opposition to the introduction of such standards, and he called on those unnamed countries to rethink their positions.

"Sometimes countries want to have their cake and eat it," he said. "That is, you can't at the same time want the United Nations to have perfect discipline and everything, and then resist any U.N. encroachment or interference with their own national disciplinary procedures. It makes things very difficult."

Although the United Nations can send misbehaving peacekeepers home, troop-contributing countries are responsible for their uniformed personnel, and U.N. rules can be made binding only with their agreement.

Guehenno said it is vital both the United Nations and member states "have the same understanding of what is acceptable, what is not acceptable, what is criminal, what is not."