Chief among his demands is the release of more than 2,000 political prisoners held in Burma, including opposition leader Aung San Suu Kyi. Her trial was due to resume Friday, but a judge postponed the hearing until July 10. She is accused of breaking the terms of her house arrest by admitting an uninvited American visitor, who has also gone on trial.
In addition, Mr. Ban wants to discuss multiparty elections slated to be held next year. The junta has called the elections the final stage of a road map to democracy, but exiled prodemocracy groups and Western governments have described the process as a sham that will entrench the dictatorship.
On Friday, Ban met with Army General Than Shwe, the junta chief, in the capital, Naypyidaw. He is expected to meet with opposition groups and civil society leaders during his two-day visit, the Associated Press reported. But it isn't clear if he will be allowed to meet Ms. Suu Kyi before he leaves Saturday.
A difficult task for Ban
Previous UN envoys to Burma have pushed unsuccessfully for dialogue between the current regime, which seized power in 1988, and Suu Kyi, whose political party won the last elections in 1990. They were later annulled as the military clung to power.
Western diplomats say that unless he is able to wring concessions from the regime, such as a substantial release of political prisoners, Ban's mission may fare no better.
"The UN road doesn't seem to be leading anywhere," warns a diplomat in Bangkok.
Ban has acknowledged the enormity of the task. "This is going to be, I know, a very difficult mission. But at the same time, I know that to bring changes to Myanmar, political conciliation and democratization, we need to do our best," he told reporters in Singapore on Thursday.
On his last visit in May 2008, in the wake of a massive cyclone that ripped through southern Burma, Ban convinced the regime to open its doors to large-scale humanitarian aid. Working with neighboring Southeast Asian countries, international relief agencies eventually got a foothold in the cyclone-hit areas.
That successful mission may have convinced Ban that he can get results in Burma. He has reportedly been stung by criticism of the UN's failure to protect civilians caught in Sri Lanka's civil war that ended in May and may be seeking to put his stamp on another thorny political situation.
Suu Kyi's treatment scuttles possible aid increase
In February, Secretary of State Hillary Rodham Clinton said the policy of isolating and punishing Burma hadn't changed its behavior. That raised prospects of a shift away from sanctions and an increase in Western aid programs for the poor nation, which gets far less aid than its neighbors.
But the widely condemned treatment of Suu Kyi has scuttled these expectations, at least for now, say Western diplomats who follow Burma.
Exiled Burmese activists and human rights groups, who have lobbied for greater international pressure on the repressive regime, are divided over Ban's visit and the prospects for a political thaw.
Some worry that he will go away emptyhanded – and that the regime will gain legitimacy for its road map to democracy while further isolating its critics. The number of political detainees has doubled to 2,100 since a thwarted uprising in 2007, according to Human Rights Watch.
"Ban Ki-moon ... should make it clear that the time for stalling and playing games is over and that real change is needed now," Kenneth Roth, executive director of Human Rights Watch, said in a statement.
Others welcome Ban's intervention, arguing that, even if it doesn't produce instant results, it puts Burma on the UN's agenda and sets parameters for the road ahead.
"Whether or not the [Burmese] military responds positively or not, the secretary-general has to report back to the UN, to the General Assembly and the Security Council," says Thaung Htun, a member of the exiled National Coalition Government of the Union of Burma. "Then it's the responsibility of member states to take concerted action."
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