Undated (AP) _ Hog and pork belly futures prices shot up Monday on the Chicago Mercantile Exchange after President Bush announced an offer to sell 30,000 metric tons of U.S. pork to the former Soviet republics at subsidized prices.

On other commodity markets, cattle futures were mixed; cocoa futures soared to a four-month high; precious metals fell sharply; oil futures retreated; and grains and soybeans ended mixed.

Hogs for October delivery surged 1.35 cents to 39.20 cents a pound in Chicago. August deliveries of frozen pork bellies soared the permitted daily limit of 2 cents to 34.80 cents a pound.

The rally was a response to the Bush administration's offer to subsidize pork sales to Russia and other former Soviet republics. U.S. pork producers have long lobbied for such assistance, which the government uses routinely to make U.S. wheat prices competitive on the world market.

The proposed pork sale, which is equivalent to about 66 million pounds, would be a boon to producers but it is by no means certain, analysts said.

The 66 million pounds of pork would cost about $80 million at market prices, estimated Chuck Levitt, senior livestock analyst with Shearson Lehman Brothers Inc. The proposed subsidies would reduce that figure by $16 million to $19 million, he said, leaving the targeted countries to come up with more than $60 million to buy the pork - if they want it.

Russia, the largest of the republics, has been relying on U.S.-guaranteed loans to make virtually all of its U.S. food purchases, and it has exhausted most of a $600 million package of credits it received in April.

To buy the pork, Russia likely would need new loan guarantees, which probably won't be offered until the Oct. 1, the start of the new fiscal year, analysts said.

The expectation of a two-month delay in any pork purchases explained why buying interest among futures traders was concentrated in the October hog contract. By contrast, the August contract rose just .52 cent to 43.52 cents a pound.

Analyst Dan Vaught of A.G. Edwards & Sons in St. Louis said an autumn sale would make sense because that's when hog slaughter rates typically peak each year. Plenty of pork is available then, he said, ''and if you want to keep prices up, that would be the time to do it.''

Levitt said Bush's announcement Sunday to leaders of the National Pork Producers Council at a meeting in suburban Chicago would please hog farmers but may not play as well with consumers who could see higher pork prices if the deal goes through.

Live cattle for August delivery fell .30 cent to 73.52 cents a pound on the Chicago Merc; August feeder cattle slipped .08 cent to 84.17 cents a pound.

September cocoa futures soared $64 to $1,077 per ton on New York's Coffee, Sugar & Cocoa Exchange, driven by worries about dry weather in West Africa, a key cocoa-growing region.

Precious metal futures fell sharply as millions of South African blacks joined a two-day nationwide strike that, despite at least 12 deaths, was less violent than traders expected. South Africa is the largest producer of platinum and a major source of gold.

October platinum slid $6.80 to $378.30 a troy ounce on the New York Mercantile Exchange.

On New York's Commodity Exchange, August gold fell $4.80 to $352.60 a troy ounce; September silver fell 5 cents to $3.887 a troy ounce.

Heating oil led energy futures lower on the New York Mercantile Exchange, reflecting perceptions that refiners have begun their seasonal retooling to produce more heating oil and less gasoline.

Light sweet crude oil for September delivery fell 29 cents to $21.58 a barrel; September home heating oil dropped 1.42 cents to 59.80 cents a gallon; September unleaded gasoline fell .47 cent to 59.88 cents a gallon; September natural gas fell 3.5 cents to $1.857 per 1,000 cubic feet.

Grain and soybean futures prices finished narrowly mixed on the Chicago Board of Trade after a rally led by commodity funds erased early losses.

Wheat for September delivery settled 1 cent lower at $3.16 1/4 a bushel; September corn fell 3/4 cent to $2.19 1/2 a bushel; September oats slipped cent to $1.30 a bushel; August soybeans rose 3/4 cent to $5.58 a bushel.