Agriculture Secretary John Block said yesterday that President Reagan has called for a Cabnet-level review next week of the partial U.S. grain embargo against the Soviet Union, which both Reagan and Block have criticized in the past.

The embargo was imposed by former president Carter in January 1980 following the Soviet invasion of Afghanistan. The action drew severe criticism from farmers, mostly in the Midwest, who complained they were penalized unduly by the policy move. Carter extended the embargo earlier this month.

Block, an Illinois grain farmer who was among those critics, said he does not believe the new administration will make a decision next week, but he promised that "this will be dealt with swiftly."

At his first news conference since his confirmation as secretary, Block made these other points yesterday:

The administration's budget-cutting review will touch agriculture programs, as well as others throughout the government, with more attention to the costliest. At the USDA those will include the Farmers Home Administration, dairy price supports and nutrition programs, Block said.

Food prices, which USDA economists predict could rise by as much as 15 percent this year, continue to be "a great bargain . . . an inflation-fighter." He said the "trend line" on food prices is lower than that of other basic consumer items, and he will oppose any governmental efforts to target food price increases for curtailment.

The administration will work vigorously to bolster U.S. agriculutural exports, notwithstanding some fears that such a policy could lead to higher prices for U.S. consumers.

Much of yesterday's session focused on the grain embargo -- whether and how long it will go on, whether it achieved its purposes and what will happen to U.S.-Soviet grain trade in general.

Block said the embargo was raised at a meeting of the Cabinet on Tuesday, with presidential adviser Edwin Meese III suggesting that a review be conducted by the National Security Council.

The secretary said that he proposed that the review draw on other agencies' thoughts, as well, and that President Reagan went along with the idea. Block said the issue will be dealth with again next week.

"I have always felt it was doomed to failure," Block said, "but we need to review it." Reagan, sharply critical of the embargo during his presidential campaign, had taken a similar postion since the election.

Carter last year cancelled contracts for the sale of 17 million metric tons of corn, soybeans and wheat, an amount beyond that provided for in a 1975 grain-trade agreement between the two countries. After the embargo was ivoked, the Carter administration allowed the delivery for another 8 million metric tons that were covered by the 1975 agreement.

The 1975 agreement is scheduled to expire on Sept. 30. Block said he could provide no details on extension of the accord.

Block also said that, should the administration decide at any time in the future to embargo food or grain exports, he expects "to have a full and fair share of influence" with policy makers.