But in the past week the Burmese government has finished drafting the country's new constitution, and announced plans to hold a referendum in May and new elections in 2010. This effectively leaves the envoy with little left to do while he is there – though he will certainly press for the release of detained opposition leader Aung San Suu Kyi.

Gambari is expected to arrive in Rangoon next Friday after visiting Tokyo, according to U.N. sources who do not wish to be identified. Burmese authorities have agreed to allow Gambari to visit Burma in the first few days of March, according to a Chinese diplomat in the region. Gambari himself remains coy about the forthcoming visit, but told journalists in Jakarta this week that he was hopeful of visiting Burma in the first week of March.

"Beijing and Delhi have both been pushing the Burmese leaders to allow Gambari back as soon as possible," an Indian diplomat told Mizzima recently on condition of anonymity. "The generals couldn't really ignore the strong advice of their two biggest neighbours," he said. Earlier this week Gambari held discussions in Beijing with senior Chinese officials, including the foreign minister, on Burma and was assured of their support.

But the military government's recent announcement that it plans to hold democratic elections in two years time, after conducting a referendum on the new constitution in May, effectively puts an end to Gambari mission. "It's easy for the junta to agree to Gamabri's visit now, as he really has nothing to talk about," a Bangkok-based diplomat close to the international mediation efforts with the Burmese military told Mizzima, but declined to be identified.

"Than Shwe's decision to set a time-table for the road-map was a strategic move to block both Maung Aye – his deputy -- from assuming power later -- and the international community, especially Gambari, from playing a role in the process," he added.

When Gambari visited Burma last time, in November, he had a three-pronged approach. He asked to the be involved in a constitutional review process after the National Convention had completed drawing up the guidelines, he wanted to encourage the regime to make the national reconciliation process more inclusive and involve pro-democracy leader Aung San Suu Kyi and the National League for Democracy, and to set up a Poverty Alleviation Committee.

After visiting the countries of region, Gambari remains upbeat. "What is important for us is to work together with them [the military government], with the neighboring countries, with ASEAN and the international community to enhance the credibility of this constitutional process, and to make national reconciliation more inclusive," Gambari said in Jakarta after meeting the Indonesian president and foreign minister.

At best, Gambari has now been left with a limited role – possibly in helping with economic reform. "The junta will ask him to approve the new constitution that has just been finalised, and give it credibility in the hope of deflecting further international pressure," a government source said. "That's what they would see his role as in any constitutional review process."

Although the government has officially announced the completion of the drafting of the constitution and copies are available in government offices, no one has yet to see a copy. Diplomats and opposition politicians contacted by Mizzima this week have all drawn a blank in their efforts to obtain a one.

"A drafting committee completed the constitution in mid-December," according to a government source. But it has been held under wraps while Than Shwe mulled over what to do next.

Nor has Than Shwe ever had any intention of making the national conciliation process inclusive. There was never a role for Aung San Suu Kyi or the NLD. So any efforts by Gambari on this issue were destined to be rebuffed entirely.

The only question that remains to be answered is when will the opposition leader now be released from house arrest? In previous discussions with U.N. envoy Razali Ismail, the then prime minister and military intelligence chief, General Khin Nyunt, said she would be freed after the constitution was ratified, according to sources close to the U.N. envoy at the time.

Gambari could hope to get a renewed commitment that this will happen soon after the referendum in May. While in Indonesia, Gambari told reporters there that he would certainly raise the issue of Aung San Suu Kyi's continued detention and her participation in the proposed elections in 2010.

The main problem for the U.N. envoy is that he is likely to only be given access to lower level officials.

"Than Shwe is still furious at Gambari because he smuggled out a letter from Aung San Suu Kyi [which he made public in Singapore on his way back to New York to report to the UN Secretary General] last time," the Chiang Mai-based Burmese academic Win Min told Mizzima.

"He didn't see Gambari then, and Than Shwe is even less inclined to meet him this time." This is something sources close to the U.N. envoy admit is almost certain to be the case again. It is even possible he will be denied access to Aung San Suu Kyi and the opposition.

"As long as Gambari is able to stress the international community's concerns to the generals – and Than Shwe hears it, even if its second hand -- that will be an important measure of whether this forthcoming trip is a success or not," a spokesman for the Burmese opposition abroad, Zin Linn told Mizzima.

The planned referendum must be "free and fair" and international election monitors allowed to observe the process, he said. Aung San Suu Kyi must be freed as soon as possible and allowed to participate in the forthcoming elections; and the NLD must be allowed to stand in the elections without restrictions or harassment.

"The junta must be under no illusions that only a credible vote will satisfy the international community," according to a Rangoon-based western diplomat.

The ASEAN foreign ministers at their retreat in Singapore earlier this month stressed the same message. "Nyan Win [the Burmese foreign minister] was told in no uncertain terms that while the referendum was considered a domestic matter – it was essential that is was a credible process," according to a Southeast Asian diplomat who was at the meeting.

But Gambari may find even delivering this message hard going. The Burmese junta has hinted in several ways that the U.N. envoy and the U.N. as a whole has no further role to play in Burma's national reconciliation process or the proposed political reforms.

Gambari is likely to find his next visit to Burma is merely a final courtesy call, and the international community will be left to consider how it plans to engage the regime in the future.