BANGKOK — UN Secretary-General Ban Ki-moon urged Burma's military government Tuesday to release political prisoners before upcoming elections, saying "it is not too late" to make the polls more fair and inclusive.

Myanmar's Nov. 7 elections will be the country's first in 20 years. The polls have widely been denounced as rigged to ensure that pro-military candidates will dominate. The country's leading opposition figure, Aung San Suu Kyi, is unable to seek office and remains detained, along with about 2,100 other political prisoners.

"We'll be expecting that this election will be a fair one, a credible one and an inclusive one," Ban told reporters in Bangkok at the start of a four-country Asian tour. "In that regard, it is not too late, even now, that by releasing the political detainees, they can make this election more inclusive and participatory."

The junta has ignored past UN demands to free political prisoners. Suu Kyi has been detained for 15 of the past 21 years.

"I do expect and hope this election to be an inclusive and transparent one," Ban said. "This will be a test of Burma's government, how they will be able to meet expectations of the international community."

The UN chief spoke after meeting with Thai Prime Minister Abhisit Vejjajiva in Bangkok. He was headed later Tuesday to Cambodia, followed by Vietnam for a weekend summit of Asian leaders. His last stop will be China.

Ban said he was looking forward to having "a very constructive dialogue" with Myanmar Prime Minister Thein Sein during a bilateral meeting at the summit in Hanoi.

About 1,000 police were mobilized in Bangkok for Ban's visit to prevent anti-government protesters who had threatened to mobilize. A small group protested outside the UN office but the rally was peaceful.

Thailand's army chief, Gen. Prayuth Chan-ocha, warned so-called Red Shirt protesters who staged paralyzing protests earlier this year that rallies were "absolutely prohibited" during Ban's visit to avoid "embarrassing" Thailand.

At least 91 people died and 1,400 were injured in violence connected to protests that lasted from March through May, staged by Red Shirt protesters demanding Abhisit call early elections. The protesters blockaded Bangkok's commercial heart for weeks before the army moved in to clear the streets. Most of the casualties were protesters.

Human Rights Watch issued a statement urging Ban to use his Asian tour "to publicly address pressing human rights issues in the region."