Japanese Prime Minister Yukio Hatoyama's apparent lack of consistency in his remarks about what kind of solution should be sought in the dispute over the relocation of the US Marine Corps' Futenma Air Station could eventually shake the foundation of his administration, observers said.

A working group of foreign and defence ministry officials from Japan and the United States started talks over the relocation of the Futenma facility Tuesday. Though the two sides agreed the issue needs to be quickly resolved, the US side would not compromise on its basic stance that the current relocation plan should be carried out.

Both sides need to compile budgets related to the relocation soon, while settling the issue could become more difficult if a decision is not made before a mayoral election is held in the city where the alternate facility to replace the air station is to be located under the current plan.

If no conclusion is reached by the end of the year, it is inevitable that the disarray will deepen, and it is possible that the issue will cast a shadow on the management of the Hatoyama administration.

At Tuesday's meeting, foreign minister Katsuya Okada said, "I've kept it strongly in mind that this issue should be concluded as quickly as possible."

His remark was based on his visit to Okinawa Prefecture on Sunday and Monday, during which he heard numerous objections to his plan to integrate the Futenma Air Station into US Kadena Air Base.

Defence minister Toshimi Kitazawa also mentioned that the compilation of the fiscal 2010 budget needs to be finished by the year-end, and said, "If possible, we have to reach the conclusion by the end of this year."

The US side insisted that a plan to relocate Futenma Air Station to shores off Camp Schwab in Nago in the prefecture, which the two governments had agreed on, should be carried out as planned.

Since no other alternative locations have been found, Okada said the defence minister and he shared the view that the path to the resolution "will be very narrow and tough".

A senior foreign ministry official said, "The foreign minister seems to finally have understood how difficult the issue is."

In addition, if a candidate opposing the current relocation plan wins in the Nago election in January, not only will the relocation of Futenma Air Station become impossible but the whole realignment of US forces in Japan, including a planned move of 8,000 US marines to Guam, may be totally nullified.

The Japanese and US sides have been split over the purpose of the working-level negotiation from the beginning.

The day after Friday's summit meeting between Hatoyama and US President Barack Obama, the difference between the views of the two leaders quickly surfaced.

While Obama said the working-level negotiation is for carrying out the past bilateral agreements about the bases, Hatoyama said such a negotiation was unnecessary "if the agreements are to be the preconditions".

On Tuesday, Okada told US Ambassador to Japan John Roos that the working-level negotiation is for reexamining the Futenma relocation plan, and Roos accepted this interpretation of the Japanese side's position.

The two seemed to have prevented the discussions from stalling over the purpose of the talks. However, even if Okada and Kitazawa reached an initial conclusion, it is still uncertain whether the prime minister will be convinced by the outcome.

Though Hatoyama told reporters Tuesday he would respect the conclusion reached by the working-level talks, he repeatedly made seemingly contradictory remarks.

Some political observers assume that Hatoyama is constrained by the Social Democratic Party, which has urged that Futenma Air Station be moved out of the prefecture or even out of the country, because he values and wants to protect the stability of his coalition government. Thus, it is likely that Hatoyama's position might change again.

In fact, SDP leader Mizuho Fukushima, who is also state minister for consumer affairs, said after an informal Cabinet meeting Tuesday, "I hope the issue will be firmly tackled based on the three-party accord."

It is predictable that the SDP will threaten to leave the coalition if the current relocation plan is agreed upon.

Also, the DPJ's prefectural chapter in Okinawa Prefecture has been united in calling for the air station to be moved out of the prefecture. Some in the prefectural chapter said that the local branch as a whole may leave the DPJ if the current relocation plan is approved.

Actions by the SDP and the DPJ's local chapters may trigger wider movements that shake the foundations of the Hatoyama administration.

But if the government dares to revise the current relocation plan, the negative impact on Japan-US relations will be immeasurable. It is certain that criticism of the Hatoyama Cabinet will increase.

At Friday's summit meeting, Hatoyama and Obama agreed to start new rounds of governmental talks to deepen the Japan-US alliance. Failure to resolve the Futenma issue is very likely to adversely affect these bilateral talks. It is inevitable that Japan's diplomatic power will decline if the Japan-US alliance is shaken.