The leverage of Canberra and Wellington over the Pacific islands in the UN has been weakened by the rise of a new mini-block in the UN General Assembly, called the Pacific Small Island Developing States group, or P-SIDS, as an alternative to the Pacific Islands Forum grouping, the regional association which includes Australia and New Zealand. The forum expelled Fiji last year over its failure to hold an election, as Commodore Frank Bainimarama had earlier offered.

''This seems to be affecting the dynamics of voting in the United Nations now,'' says Dr Richard Herr, a University of Tasmania specialist on international relations who has closely watched the South Pacific for 30 years. ''When the island states get together to caucus they tend to caucus under the P-SIDS banner rather than under the forum banner. If done deliberately, it's done to exclude Australia and New Zealand from discussions.''

The UN envoy for Fiji, Peter Thomson, said the new grouping evolved about two years ago as Fiji was being expelled from the forum, despite hosting its headquarters and other regional institutions. It had now grown to an active caucus, meeting frequently with other UN groupings.

A contact with the Arab League led to a P-SIDS summit meeting in Abu Dhabi with the Arab states, which Commodore Bainimarama attended, and the start of an official aid program from the Gulf states to the South Pacific.

The shift ties the island states more closely to the Asia Group in the General Assembly, to which they belong, while Australia and New Zealand belong to the Western European and Other Group, affecting how they vote for rotating seats in the Security Council and UN committees.

Dr Herr said there was resentment among the island states at Canberra's insistence at getting the Pacific Islands Forum to declare a preference for Canada's candidacy for the Security Council in last month's election for two seats in 2011-13.

''There was a sentiment that Australia went too far, that it was pushing its own objectives to get a seat down the track.'' Canada unexpectedly lost to Germany and Portugal in the secret ballot of all General Assembly members.

The Fiji envoy, Thomson, said he told Ottawa he would vote against it, because of its lack of presence in the South Pacific, but declined to say what he knew about the other P-SIDS votes. ''You can analyse the votes and see they [the Canadians] didn't do well,'' he said.

The Pacific island states have 12 votes in the General Assembly, a block that could become critical in Australia's looming contest with Finland and Luxembourg in 2012. ''What the development of this new arrangement is showing is that using the forum in sanctions against one of its members has had some dysfunctional consequences,'' Dr Herr said.