Leaders of Lithuania, Latvia and Estonia are calling on the United States to pressure the Soviet Union into ending its crackdown on the three renegade Baltic republics, diplomatic sources say.

The officials were taking their case to Secretary of State James A. Baker III and to Capitol Hill Tuesday amid almost daily expressions of strong administration concern over Moscow's policies toward the Baltic states.Among other recommendations, Baker was expected to hear an appeal for cancellation under certain conditions of next month's scheduled summit in Moscow between President Bush and Soviet President Mikhail Gorbachev.

Baker was meeting with Dainis Ivans, a vice president of Latvia; Bronius Kuzmickas, a vice president of Lithuania; and Endel Lippmaa, Estonian minister without portfolio.

In preliminary discussions with U.S. officials, the Baltic leaders have hinted that the United States should use economic pressure on the Soviet Union in order to persuade the Kremlin to respect their sovereignty.