Soviet President Leonid Brezhnev and Czechoslovak President Gustav Husak, meeting in the Crimea, issued a communique today stressing the importance of greater economic cohesion within the Soviet Bloc to offset the effect of American economic sanctions.

The communique added, however, that the Soviet Union and Czechoslovakia would not cut themselves off from "mutually beneficial" trade ties with the West.

The joint statement, as distributed by the official Soviet news agency Tass, said Brezhnev and Husak attached "great significance" to a planned summit meeting of bloc countries to discuss economic problems. There is speculation in Moscow that such a meeting, which has been talked about for at least a year, could be held in the next few months.

Brezhnev made a public appearance, his first in nearly a month, at the meeting in a Crimean resort. The announcement scotched rumors circulating here that Brezhnev, 75, was too ill to receive visitors. There had been suggestions that he would drop his practice of holding consultations with the heads of ruling Communist parties during their summer holidays.

Husak is the first Soviet Bloc leader reported to have conferred with Brezhnev this summer. The president of Afghanistan, Babrak Karmal, and the Mongolian Communist Party leader, Yumjagim Tsedenbal, both visited the Soviet Union this month, but there was no official report that they had been received by Brezhnev.

Western diplomats here have speculated that Brezhnev, who was reported to be seriously ill earlier this year, had wanted to conserve his energy for a summit with President Reagan that is planned for October.

Soviet television news bulletins today carried two still pictures of Brezhnev and Husak but no news film of their meeting. The Soviet president and Communist Party chief appeared to be in no worse shape than he was last month when he met in Moscow with the Bulgarian premier. Brezhnev left Moscow July 3 for his annual vacation in the Crimea.

Judging from the communique, the central theme of Brezhnev's discussions with Husak was the troubled state of their countries' economies. This contrasts with last year, when the fallout from the Polish crisis and the still unresolved issue of how to deal with the independent Polish union Solidarity formed their main preoccupation.

U.S. trade sanctions against the Soviet Union and Poland, combined with the problems several Soviet Bloc countries are encountering in paying off hard-currency loans incurred over the past decade, have exacerbated long-standing domestic economic problems. The Kremlin has responded by calling for greater economic integration within the Soviet-led trading community Comecon--a call that has been supported by the bloc's economically weaker members such as Romania.

Early last month, a meeting of Comecon premiers was held in the Hungarian capital, Budapest.

[Tass also reported that Deputy Premier Konstantin Katushev, once believed to be a possible successor to Brezhnev, has been relieved of his duties and appointed ambassador to Cuba. The sudden switch of Katushev, 54, appeared to be part of a gradual slide from grace which began in the late 1970s, said Western diplomats quoted by Reuter.]