YANGON, Myanmar - Myanmar has invited the U.S. and European Union to send observers to monitor April elections, an American official said Wednesday, a first for the long-isolated country seeking to convince the West to lift crippling sanctions.

Myanmar's government has not yet announced that it will allow international monitors into the country, but word has leaked out from around the world.

The 10-nation Association of Southeast Asian Nations said in a statement Tuesday that Myanmar had invited its neighbouring countries to send a five-member delegation along with two parliamentarians and media representatives from each country.

On Wednesday, the U.S. Embassy in Yangon said the invitation had also been extended to Washington and the European Union, which are dialogue partners of ASEAN.

"We are encouraged that the authorities have invited international representatives as observers, including from ASEAN, the EU and the United States," embassy spokeswoman Adrienne Nutzman told The Associated Press. She said an invitation was sent to Washington.

"It's notable that the Burmese government will also allow some journalists from these countries to observe the process, demonstrating increased openness to the foreign media," Nutzman said.

She declined to give details of how many American monitors would be allowed and if the U.S. had accepted the invitation, deferring further comment to Washington.

It was not immediately clear what sort of access would be granted to the observers.

The British Embassy received a note from Myanmar's Ministry of Foreign Affairs saying it could send a representative from the mission to participate in an "observation tour" on election day, said embassy official Joe Fisher.

After half a century of military rule, Myanmar's army ceded power last year to a nominally civilian government. Since then, President Thein Sein has surprised Western governments by making several dramatic changes, including opening up next month's byelections to the opposition party of Aung San Suu Kyi, releasing hundreds of political prisoners, signing truces with rebel groups and easing restrictions on the media.

But the international community says more progress is needed, including releasing all remaining political prisoners and putting an end to ethnic violence and human rights abuses, which rights groups say continue despite the unprecedented reform campaign.

The U.S., EU and others say the polls will be "a key test" of the government's commitment to reforms.

American officials have called for a free and fair election in April and say the conduct of the byelections will be a major factor in the West's decision to lift economic sanctions imposed on Myanmar during the military junta's rule.

The April byelection is being held to fill 48 parliamentary seats vacated over the past year.

Suu Kyi, a former political prisoner and 1991 Nobel Peace Prize laureate, is running for one of the seats in parliament and has generated enormous support for her party in a nationwide campaign tour. If Suu Kyi wins her seat, it would give her a voice in government for the first time after decades as the country's iconic opposition leader.

Suu Kyi's National League for Democracy party overwhelmingly won a 1990 general election but the military refused to let it take power.

The opposition party boycotted a 2010 general election, saying the rules were unfair. It agreed to rejoin electoral politics last year when Thein Sein's government began implementing democratic reforms.

Myanmar's former ruling junta had rejected international bids to observe the last two elections, in 2010 and 1990.