President Kumaratunga's dismissal of 39 junior ministers will hit Sri Lanka's peace process, the prime minister says.
The prime minister is critical of the move
Ranil Wickramasinghe wrote to the president saying her actions were hampering government efforts to meet its peace process commitments.
President Chandrika Kumaratunga and Mr Wickramasinghe are locked in a bitter power struggle ahead of the April poll.
She believes Mr Wickramasinghe has made too many concessions in negotiations with Sri Lanka's Tamil Tiger rebels.
In his letter to President Chandrika Kumaratunga, the prime minister complained he was not consulted about the decision to remove the 39 ministers.
"I have to point out that through these actions, you are seriously jeopardising the implementation of the peace process," he said.
He said that the president's decision to dismiss all non cabinet ministers means three key ministries involved in rehabilitation and relief for the north east have been abolished.
"The abolition of these ministries will create serious difficulty in carrying forward the basic elements of the peace process," Mr Wickramasinghe said.
A government spokesman, said snap elections called by the president would cause instability and deprive Sri Lanka of donor funds.
GL Peiris said millions of dollars of credits from the World Bank for poverty alleviation in the south of the island had been delayed by the calling of elections.
Ms Kumaratunga's move to dismiss the ministers is said to have been aimed at preventing ministers from misusing official assets to help their re-election campaigns.
A letter from the president's office to the ministers complained that vehicles, office equipment and important documents were already being taken away from ministries illegally.
Supporters of the president say her move to hold fresh elections will save the country from anarchy.
The power struggle between President Kumaratunga and Prime Minister Wickramasinghe erupted in November when the president took over three of his top ministries, accusing him of making too many concessions to Tamil Tiger rebels during peace talks.
The conflict has killed about 64,000 people, displaced one million and held back the island's growth and economic development.
The Colombo stock exchange lost more than 10% in value on Monday, the first day of trading after the news of elections.
The loss was the second largest in the history of the exchange.