"This is a dangerous move and certainly China will oppose it," Wang told reporters at the UN headquarters in New York.

"It will split the house and destroy the unity and also derail the whole process of discussion on big UN reforms," Wang said.

China has opposed Japan being granted permanent status on the Security Council, demanding it first correct its attitude to its wartime history. Tensions between the two countries have risen in recent months.

Brazil, Germany, India and Japan have formed a group, called G4, to lobby for permanent seats on the Security Council.

It has circulated a draft resolution, which could be voted on at the UN General Assembly in September, proposing a 25-member Security Council, 10 more than now, with six new permanent members.

Wang said China leaned toward a rival plan, proposed by Italy, Mexico and Pakistan, to enlarge the Security Council to 25 members, but without additional veto-wielding permanent members.

"We see many good points in their formula because this will expand the Security Council and this will give certain members who they believe are important a longer term," he said.

In the Italy-Mexico-Pakistan plan, some non-permanent members could be re-elected at the end of their two-year stints on the Security Council, unlike the current practice.

The G4 nations plan to put their motion to the General Assembly if they are certain they will get the support of two thirds of the 191 UN members so that it will be passed.

Meanwhile, Japan said yesterday it still hoped to persuade China to accept a historic expansion of the UN Security Council after Beijing made clear it opposed a four-nation bid for permanent seats that includes Tokyo.

China says Japan -- which is seeking seats with Brazil, Germany and India -- must show more remorse for its aggression in the first half of the 20th century before it deserves a prestigious UN seat.