More than 100 countries complained Monday that talks on a conventional arms trade treaty had gone "backwards" from a vow to conclude a strong accord on the $80 billion a year trade.
The major western powers, which expressed confidence that an accord could be reached, face tough criticism over the treaty as talks at the UN headquarters entered the final straight.
A group representing 103 countries blasted the latest text as a step "backwards."
A statement by the 103, read by Ghana at the negotiating conference, said there were too many "loopholes" in the proposed treaty. They said it was not tough enough on ammunition, and questioned the definition used for small and light weapons.
"Certain central aspects" of the latest draft treaty "have not met our expectations and some seem to be a step backwards from earlier language," said the statement by the 103 countries from every continent.
While "there are some improvements in it, we are still concerned about the apparent lack of movement with regards to some issues and with the movement of others, in the wrong direction," said Mexico's Vice Foreign Minister Juan Manuel Gomez Robledo, reading a statement by 11 Latin American states.
The Arms Trade Treaty talks opened on March 18 and must finish on Thursday.
The aim at the start had been to produce a treaty on small arms, tanks, warships, combat aircraft, ammunition and missile launchers.
Any accord must be by consensus and the conference is haunted by the last attempt in July, which collapsed in failure with the United States and others demanding more time to consider the text.
"I think we are moving in the right direction both in terms of substance and of process," said Jo Adamson, chief British negotiator at the talks.
"We continue to work on those areas where we'll be seeking improvements," she added.
"The overall drafting of the text is tightened up and it looks more like a treaty," said another European diplomat, on condition of anonymity. The diplomat highlighted improvements such as the inclusion of an article on the diversion of weapons and the need for states to set up a national checks on its arms trade.
Germany's chief negotiator, Jorg Ranau, told the conference the latest text had "important improvements," but "critical amendments still need to be included."
The major powers, who are the major arms producers -- the United States, Russia, France, Germany, China and Britain -- have sought an accord that does not threaten their arms industries and interests, said diplomatic observers.
The United States has refused to allow ammunition into the main body of the treaty, saying it is too difficult to monitor the trade. China had opposed tough conditions on arms "gifts" which it often makes to allies without any cash changing hands.
Non-government lobby groups said the western powers are making too strong an effort to water down the treaty to get the major producers to sign on.
"There is too much talk of consensus," said Anna MacDonald of Oxfam. "This treaty must reflect the views of Africa and Latin America and all parts of the world that are affected by armed violence and conflicts."
"We are concerned that there is a too narrow range of weapons covered, that ammunitions are not properly covered and the criteria section, by which a government says yes or no to a transfer, has got to be strengthened," MacDonald said.