The United States plans to reopen negotiations with the Soviet Union soon on a new cultural and scientific exchange agreement and on establishing consulates in New York and Kiev, the State Department said yesterday.

Both sets of talks were suspended by the United States to protest the 1979 Soviet military intervention in Afghanistan.

The New York Times reported yesterday that the Reagan administration has proposed their resumption and that Moscow has agreed.

In response, the State Department said that it is U.S. policy to "explore with the Soviets those areas in which our two countries can cooperate to our mutual benefit." It refused to say that negotiations are in the works, but the department's statement noted that these "are two areas where we hope progress will prove possible."

The statement also sought to play down the idea that the projected talks represent any shift in U.S. policy or a relaxation of the generally tough line that President Reagan has maintained in East-West relations.

"Such steps do not mark any change in our approach to the Soviet Union," the statement said. "We remain deeply concerned about their military buildup, their conduct in places like Afghanistan and the Middle East and their human-rights violations. We will continue to act to deal with problems in all of these areas."

Department officials said privately that the move is consistent with the policy outlined by Secretary of State George P. Shultz several weeks ago of reacting firmly to aggressive Soviet behavior, while signaling a willingness to improve relations in areas where the Soviets are willing to cooperate.

The administration has shown a particular interest in pursuing cooperation in fields where it believes the United States clearly has something to gain.

On Thursday, Agriculture Secretary John R. Block signed a five-year, grain sale agreement that had been sought by American farmers.

Accords on cultural and scientific exchanges and expansion of consulates are also regarded by U.S. officials as being of potential benefit to U.S. interests.