Thu Oct 4, 1:37 AM ET

WASHINGTON - US senators demanded intense US pressure on China and India to force them to sever ties with Myanmar's junta after a violent crackdown on protests by monks and democracy activists.

High-profile lawmakers wanted to know how the United States could leverage its relationship with the two giant powers for the advantage of Aung San Suu Kyi's democracy movement.

"China needs to make it clear that it's unacceptable that those monasteries have been cleared of monks, that people have been loaded into trucks and driven off into God knows where," said Democratic Senator John Kerry.

Kerry warned at a hearing of the Senate Foreign Relations committee's Asia sub-panel that if China did not use its close economic relationship with Myanmar to forge change, the 2008 Olympics in Beijing would be under a "cloud."

The hearing came hours after Myanmar's military rulers kept up the pressure on their people, after last week's bloody crackdown on protesters.

Troops, who last week killed at least 13 and arrested over 1,000 people to suppress the largest pro-democracy protests in nearly 20 years, made new arrests and mounted patrols to keep the population on tenterhooks.

Senate Republican minority leader Mitch McConnell, author of legislation imposing US economic sanctions on Myanmar, joined Wednesday's hearing and complained that efforts to pressure the junta were weakened without Chinese and Indian backing.

"China and India are the two biggest players in Burma (Myanmar). Their attitude seems to be largely it'd be bad for business to start siding with the pro-democracy forces," said McConnell.

But Democratic Senator Jim Webb said that despite a punishing US and European range of sanctions on Myanmar, it was unclear what more the West could do to support Aung San Suu Kyi.

"You have a type of pressure which is driving authoritarian governments toward like partners, China being the classic example with respect to Burma," Webb said.

Scot Marciel, deputy assistant secretary of state for East Asian and Pacific Affairs, said President George W. Bush's administration had been doing its best to pressure China.

"While we have indications that Beijing has been quietly pressing junta leaders to exercise restraint ... we think China can do more," he said.

"We have been pressing and we will continue to press Beijing to do more."

The US House of Representatives on Tuesday voted by 413 votes to two for a resolution calling for the release from house arrest of Aung San Suu Kyi, and an immediate halt to attacks against civilians by the junta.

It also called on China to pressure Myanmar's generals and for the UN Security Council to act on the crisis.

A similar resolution passed the Senate on Monday.

Last week, the Bush administration slapped visa bans on more than 30 members of the Myanmar junta and their families, in addition to a punishing range of already enforced economic sanctions.

Adding to the symbolism of the hearing, US First Lady Laura Bush called for Myanmar's reclusive generals to "step aside" and urged the UN Security Council to issue a resolution calling for a peaceful transition to democracy.

"The United States believes it is time for General Than Shwe and the junta to step aside, and to make way for a unified Burma governed by legitimate leaders," she said in a statement.

"We urge other governments to join the United States in condemning the junta's use of violence, and in working toward freedom for Burma," she said.

Washington does not recognize the name Myanmar and continues to call the country Burma.

The protests first erupted in mid-August after a massive hike in the price of fuel, but escalated two weeks ago when the revered monks emerged to lead the movement, drawing up to 100,000 people onto the streets.

Chinese Premier Wen Jiabao Saturday urged Myanmar to seek stability in a peaceful manner and work towards democracy and development.

India on Monday urged Myanmar's military regime to launch a probe into its violent crackdown on pro-democracy protests, the foreign ministry said.

But critics of both nations in Congress say that is not enough.