(Adds details on the migrants coming ashore)
* Myanmar lands 727 migrants after boat kept offshore for days
* U.S. says minority Muslim Rohingya should have passports
* Bangladeshis, Rohingya from boat separated
* Govt said moved some to Bangladesh border
* United Nations estimates 2,000 still at sea
By Randy Fabi and Aubrey Belford
JAKARTA/MAUNGDAW, Myanmar, June 3 (Reuters) - Myanmar brought ashore more than 700 "boat people" it had kept at sea for days aboard a seized vessel, as the United States on Wednesday called on the country to help solve a migrant crisis by recognising the rights of its Muslim Rohingya minority.
U.S. President Barack Obama has sought to make Myanmar's transition to democracy a legacy of his presidency, and Washington is stepping up pressure on the Southeast Asian nation to tackle what it sees as the root causes of an exodus of migrants across the Bay of Bengal that the region has struggled to cope with.
The 727 migrants were found drifting in the Andaman Sea on Friday in an overloaded fishing boat that was taking on water. Myanmar's navy brought the vessel to the coast of western Rakhine state, where they disembarked on Wednesday.
Two migrants who came ashore told Reuters that 200-300 people on the boat were Rohingya, and the remainder Bangladeshis. Myanmar authorities have said they believe most are Bangladeshis.
Authorities separated Bangladeshis from Rohingya, before taking the Bangladeshis away in buses, a Reuters witness said.
The Rohingya were kept inside a warehouse at the landing point, where they were watched over by dozens of police, the witness said. It was unclear if the group was moved later, as journalists were asked to leave the site.
No aid personnel had access to the site at that point, the Reuters witness said. The U.S. called on Myanmar authorities to allow aid agencies access to the migrants.
"We are strongly urging authorities to ensure the full protection and well-being of the migrants and to allow for immediate humanitarian access and assistance, including urgent medical care and adequate accommodation," a U.S. embassy spokesman said.
Women and children from the boat were taken to the same location where another 200 migrants, who came ashore on another boat in May, are being held, Myanmar's Ministry of Foreign Affairs said in a statement on Wednesday.
The rest were taken to near the border with Bangladesh, the statement said.
Many of the more than 4,000 migrants who have landed in Indonesia, Malaysia, Thailand and Myanmar since the Thai government launched a crackdown on people-smuggling gangs are Rohingya who say they are escaping persecution.
Myanmar officials had said last month that the 200 people on the boat that came ashore in May were mainly economic migrants from Bangladesh. But interviews by Reuters found more than 150 Rohingya had earlier been on the same boat, but were quietly whisked off by traffickers before authorities brought the vessel to shore.
Myanmar does not recognise its 1.1 million-strong Rohingya minority as citizens, rendering them effectively stateless. Many have fled the apartheid-like conditions of the country's Rakhine state. Myanmar denies it discriminates against them.
"Rohingyas need to be treated as citizens of Burma," U.S. Assistant Secretary of State Anne Richard told reporters at a press briefing in Jakarta, using the country's former name.
"They need to have identity cards and passports that make clear they are as much citizens of Burma as anyone else."
Obama said on Monday that Myanmar needed to end discrimination against the Rohingya people if it wanted to succeed in its transition to a democracy.
Politicians in Myanmar were focused on a historic general election scheduled for November, Richard said, which was hindering political discussion of the status of the Rohingya, who are deeply resented by many of Rakhine's Buddhist majority.
Images of desperate people crammed aboard overloaded boats with little food or water has focused international attention on the region's latest migrant crisis.
The crisis blew up last month after the Thai crackdown made it too risky for people smugglers to land their human cargo. Smugglers abandoned boats full of migrants at sea.
SUU KYI SILENCE
Richard said she would like to see all Myanmar's political leaders address the issue. Opposition leader and Nobel Laureate Aung San Suu Kyi has faced international criticism for failing to speak out on behalf of the nation's many ethnic groups, including the Rohingya.
"We would love to see all Burmese leaders speak up on human rights and to realise that they should help the Rohingya," Richard said. "The boats are not going to wait until December - the people on the boats need help right now."
At an international meeting on the migrant crisis in Bangkok on Friday, Myanmar bristled when the United Nations raised the citizenship issue and when other delegates blamed the country for the problem.
"You cannot single out my country," said Myanmar's head of delegation Htein Lin.
Richard said that the United States was not considering imposing sanctions on Myanmar over the issue, but that sanctions were always "in the diplomatic toolbox".
Obama has invested significant personal effort and prestige in promoting democracy in Myanmar, which emerged from 49 years of military rule in 2010, travelling there twice in the past three years.
The U.S. president said in a routine note to Congress last month that Washington - while not curtailing engagement with Myanmar - would maintain some sanctions on the country.
"We really hope we are working with a Burma that is on a path to being a more responsible member of the international community," Richard said.
(Additional reporting by Soe Zeya Tun; Writing by Simon Webb; Editing by Alex Richardson and Rachel Armstrong)
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