The 30-day freeze on food prices at the A&P supermarket chain will end Sunday and new higher prices will take effect immediately on some products, officials said yesterday.

At the same time that some prices go up, A&P will mark down prices on 200 selected items as part of a new two-week "low-price" program.

And two other retailers, Safeway and Dart Drug, announced yesterday that they are extending their price freezes for another 30 days.

Details weren't available on the number of items which will go up in price at A&P or on the amount of the price increases. But Michael Rourke, a representative of the chain, said that bacon, canned goods and other items which were on sale at the time the freeze took effect March 6 are most likely to show price increases.

"They (items on special) were frozen at a very low price," he said.

Meantime, the A&P chain will reduce prices on about 200 items for 2 weeks beginning next week in a new "low price" program that is intended to take the place of the price freeze.

In explaining the switch from the freeze program, which encompassed about 1,600 items in an A&P supermarket, to the "low price program, which will cover 200 items, Rourke said that the chain no longer could absorb the wholesale price increases received during the past month.

"Our suppliers continued to make increases -- especially on products containing sugar," he said. "So we made the decision to take 200 items . . . covering all departments throughout the store . . . and reduce prices on them."

A&P operates 1,489 supermarkets nationally and 112 in the Washington-Baltimore area. The chain is the third largest in the nation.

Jonathon L. Scott, chairman of A&P, will be among the food and drug store officials meeting today with President Carter at the White House to discuss prices.

The price freezes implemented last month by a number of companies were in response to suggestions made in letters and phone calls by Esther Peterson, Carter's consumer adviser, who urged a voluntary price ceiling program to "ease the inflationary pressures that are causing such hardships for all consumers."

Peterson's office said yesterday that 42 retailers have been invited to meet with the president "to recognize their efforts" in freezing prices as an anti-inflation effort.

Among retailers who have announced plans to extend price-freeze programs for an additional 30 days is Safeway, the nation's largest supermarket chain. Safeway operates 120 stores in the Washington metropolitan area.

"At the request of the White House, we have extended our nationwide retail price freeze for an additional 30 days," said Peter A. Magowan, Safeway's chairman.

Safeway's price freeze includes 180 products sold under its private label called Scotch Buy.

Dart Drug also announced yesterday that it has extended its price freeze for an additional 30 days on 500 items, including Dart brand household and soft goods. The chain has about 75 stores in the Washington metropolitan area.

Giant Food Inc., which has about 100 stores in the Washington metropolitan area, will continue its 21-week price ceiling program as previously announced, a spokesman said yesterday.

The Giant freeze covers 275 private-brand products and about 100 generic prescriptions and drug notions.

Israel Cohen, president of Giant, will represent his company at the meeting today with President Carter.

Others in attendance will include Sheldon Fantle, president of the Peoples Drug Stores, which began a 90-day freeze in effect on all prescription drugs and house-brand products on March 12.

Retailers said yesterday that their price-freeze programs had been well received by customers for the most part. But some customers have complained that the stores raised prices on items included under the freeze programs.

David Bodenstein, a resident of Richmond Hill, N.Y., complained in a letter published in one newspaper that the A&P freeze was a "cruel hoax." He said that the chain had increased prices prior to the freeze on such items as Bokar coffee, which went from $8.89 for a three-pound container to $9.19.

But A&P officials said that Bokar brand coffee wasn't included in the freeze program.

"We said in the ads we had frozen 1,600 products -- he misconstrued that to mean all prices had been frozen," an A&P representative said. He said that confusion over the freeze was "the greatest challenge facing us."