Japan and its allies will keep pushing to achieve UN Security Council reform by September, Japan's UN ambassador has said, even as UN Secretary-General Kofi Annan again distanced himself from his own appeal that the debate be settled by then.

Ambassador Kenzo Oshima, whose country wants a permanent seat on the council, on Thursday said no matter what Annan says, talks will continue with African and other nations over its proposal to add 4 permanent seats to the 15-nation council.

"There is no change in our position," Oshima said. "We have not given up anything."

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Diplomats have acknowledged for more than a decade that the council, established in 1945, doesn't reflect the world in the 21st century, but have never been able to reach a deal on changing it.

Hopes were high that this time would be different after Annan told the 191-member General Assembly in March that member states should settle the issue before a September summit of world leaders. But the debate has again stalled because of national and regional rivalries.

The Security Council currently has 10 members elected for 2 year terms and 5 permanent members with veto power including the United States, Russia, and China.

Brazil, Germany, India and Japan have proposed a 25 member council, adding 6 permanent seats and 4 non-permanent seats. The so-called Group of Four are hoping to win 4 of the permanent seats with the other 2 earmarked for Africa.