The top U.S. and Soviet military leaders, side by side at an unusual Pentagon news conference, announced Wednesday they have agreed to an extensive two-year exchange of visits to improve mutual understanding.

Flanked by the chiefs of the Soviet naval, army and air forces, visiting Chief of Staff Marshal Sergei Akhromeyev, said, "We discussed and we reached agreement on making effective the plans of military exchanges for the next two years. . . . We also exchanged letters to this effect."Akhromeyev is visiting the United States for a week as the guest of Adm. William Crowe, the chairman of the Joint Chiefs of Staff, who held a joint news conference with Akhromeyev. The invitation for the visit was extended to the marshal when he attended the Washington summit in December.

"This visit is in my view another important step in the mutual endeavors of our two countries to insure the terrible prospects of conflict are lessened," Crowe said.

He noted that the visit was historic as the first by a Soviet uniformed military leader for official discussions with his U.S. counterpart since World War II.