|Somawansa Amerasinghe, leader of People's Liberation Front, speaks at a media conference in Colombo, Sri Lanka|
The row between President Chandrika Kumaratunga and the ruling coalition's key ally, the People's Liberation Front, had been brewing for over a month. It came to a head Thursday when the front, a Marxist group, formally abandoned the government.
The Marxists and President Kumaratunga, who heads the alliance, fell out over the Sri Lankan government's plans to establish what is called a "joint mechanism" to share billions of dollars in foreign tsunami aid with Tamil Tiger rebels.
Sri Lanka was among the countries worst hit by the December 26 Indian Ocean tsunami. The rebels complain that their areas have not received a fair share of tsunami reconstruction aid.
President Kumaratunga calls the pact an opportunity to forge peace with the rebels, and overcome decades of mistrust and conflict between the two sides. International donors also support the need for such a mechanism.
The rebels have been fighting for a separate state for the country's Tamil minority. They are strongly opposed by the Marxists, and groups of Buddhist monks who represent the majority Sinhalese community.
The Marxists and the monks say Mrs. Kumaratunga's plan would confer legitimacy on the rebels, and help them establish a separate state. They have led violent protests in Colombo over the past week.
However, the main opposition United National Party says it will not take advantage of the crisis and topple the government, which is now a minority administration.
The head of Colombo's Center for Policy Alternatives, Paikiasothy Saravanamuttu, says the alliance is now weak and vulnerable, but will survive for the time being.
"I don't think there is any great enthusiasm on the part of any political party to go to elections. Therefore, the situation could conceivably last until the main opposition party withdraws its support to the government, or there is some break," said Paikiasothy Saravanamuttu.
Political analysts say the aid-sharing plan - if it does finally go through - could give a fresh lease on life to Sri Lanka's flagging peace process. Peace talks between the government and the rebels have been deadlocked for over two years, even though a cease-fire is holding.
The rebels have said a mechanism for aid distribution must be in place before they will consider restarting the talks.
President Kumaratunga is widely expected to present the aid sharing plan to Parliament next week.