PRAGUE, July 16— A Russian envoy delivered copies to President Vaclav Havel today of two letters written in 1968 inviting Soviet forces to invade Czechoslovakia to crush the "counterrevolution."
The letters were written to Leonid M. Brezhnev, who was then the Soviet leader, by five high-ranking Czechoslovak Communist Party officials who opposed the Prague Spring reform movement led by the party leader, Alexander Dubcek. Copies were made available today to reporters.
One of the letters, signed by all five officials, warns that "the very existence of socialism in our country is jeopardized." Without specifically calling for an invasion, it asks the Soviet Union to use "all the means at your disposal" to counter "the imminent danger of a counterrevolution."
Mr. Havel said the letter was secretly handed over to Mr. Brezhnev during a meeting of the five Warsaw Pact nations on Aug. 3, 1968, in Bratislava, the Slovak capital. On Aug. 18, leaders of the member nations met in Moscow and agreed to a Warsaw Pact invasion of Czechoslovakia, which took place three days later.
The letter was signed by Alois Indra, Drahomir Kolder, Oldrich Svestka, Antonin Kapek and Vasil Bilak, who were members of the Czechoslovak party's Politburo. Only Mr. Bilak, the former party ideology chief, is still alive. In his only comment so far, Mr. Bilak told the Czechoslovak press agency that the letters could be a "possible forgery."
