YANGON - Myanmar's new election laws mean the opposition National League for Democracy must expel detained leader Aung San Suu Kyi from its ranks ahead of polls this year, a spokesman said Wednesday.

Details of the Political Parties Registration Act published in state newspapers say that anyone serving a prison term cannot be a party member and that parties that fail to obey this will be abolished.

Nobel Peace laureate Suu Kyi was sentenced to three years in jail in August over an incident in which a US man swam to her lakeside home. The sentence was commuted by junta supremo Than Shwe to 18 months under house arrest.

"I have noticed that we have to expel Daw Suu. Their attitude is clear in this law," NLD spokesman Nyan Win told AFP. "I was extremely surprised when I saw this, I did not think it would be so bad."

The new law also gives the NLD 60 days to register as a party if it wants to take part in the elections, which the junta has promised some time this year. The NLD has not yet decided whether it wants to participate.

Under Suu Kyi's leadership the party won Myanmar's last elections in 1990 by a landslide but the military regime annulled the result. Suu Kyi has been in detention for 14 of the subsequent 20 years.

Suu Kyi was already barred from standing as a candidate under a new constitution approved in a 2008 referendum, under a clause stipulating that those married to foreign nationals are not eligible.

Her husband, British academic Michael Aris, died in 1999.

"The NLD also needs to reply clearly but I cannot say how we will respond," Nyan Win said.

"What I can say now is the law is meant to safeguard the constitution. It will be a very big problem for us as they asked us to obey a constitution that we cannot accept," he added.

The law also bans people from any religious order - including Buddhist monks - and members of the civil service from standing in the elections.

It is the second of five laws to have been enacted on Monday ahead of the polls, for which the junta has given no date but which are expected to be in October or November.

The first law stipulates that the regime itself will hand-pick members of the electoral commission, sparking worries but not surprise from rights groups.

"Basically, the laws will formalise what is already a repressive system leading up to the election," David Mathieson, a Myanmar expert at Human Rights Watch, said Tuesday.

Critics have said the elections are a sham designed to legitimise the ruling generals' grip on power while Suu Kyi languishes in detention.

Aung Din from the US Campaign for Burma, which uses Myanmar's former name, on Wednesday called for worldwide action in response to the new laws.

"Now, the ball is in the court of the United Nations, United States, and the international community, who have been repeatedly calling for the regime to make an inclusive, free and fair election."

The United States voiced doubt Tuesday over whether the upcoming elections would be credible amid concern over the way the military junta is drafting the laws.

"We urge the authorities to begin a genuine political dialogue with all stakeholders as a first step towards credible elections," State Department spokesman Philip Crowley told reporters.