The Czechoslovak Embassy in Washington will stop representing Cuban diplomatic interests in the United States by March, the state CTK news agency reported Tuesday. CTK quoted the Foreign Ministry as saying the grace period should permit Havana ``to cope with the new situation, without jeopardizing its interests in the U.S.A.'' The Czechoslovak Embassy has represented Cuban interests in Washington since 1977. Diplomatic and consular ties between Cuba and the United States were severed in January 1961. Interests sections enable countries to maintain diplomatic contact without having to have full-fledged embassies. A senior Cuban diplomatic official in Washington, speaking on condition he not be identified, said the Cuban government has no alternate plan in mind at present to replace the current arrangement with the Czechoslovak government. He said he assumes both the Cuban and U.S. governments wish to maintain a diplomatic presence in each other's capital and that Cuba will seek a new arrangement. The official said he had seen news reports about Prague's decision but had heard nothing officially. U.S. diplomatic activities in Havana have been carried out under the auspices of the Swiss embassy. One diplomatic source suggested that Cuba may ask the Swiss to perform that function for Cuba in Washington. The source spoke on condition of anonymity. The news agency quoted an unidentified Foreign Ministry source as saying that ``the different opinions of the two countries on the exercising of human rights'' and other fundamental differences prompted the Czechoslovak decision. Czechoslovakia has become a democracy following the revolution that toppled the Communist leadership one year ago; Cuba remains Communist-ruled. The ministry source suggested that deteriorating relations after Czechoslovakia embraced democracy contributed to Prague's decision, CTK said. He singled out the storming of Czechoslovak embassy premises in Havana in July by Cubans who claimed they were dissidents but who the Czechoslovaks believe were in the pay of the Cuban government. The invasion of the embassy ``can be rightfully presumed to have been intended to discredit the new Czechoslovak regime in the eyes of the Cuban public,'' CTK quoted the source as saying. Efforts to contact the Czechoslovak embassy in Washington by telephone were unavailing.