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By P.J. Huffstutter

CHICAGO, June 15 (Reuters) - Chicago Board of Trade corn futures slumped to fresh contract lows on Monday, with the most-active contract on a continuous basis Cv1 dropping to nine-month lows, after the U.S. and Iran said they had reached an initial deal to end their war and resume traffic through the Strait of Hormuz.

Corn futures did inch higher in the morning session on bargain buying. Wheat and soybean futures remained under pressure from the news, though the pact may hinge on events in Lebanon and defer tricky talks on Tehran's nuclear program. The memorandum of understanding is scheduled to be officially signed on Friday in Switzerland.

The news sent oil prices sharply lower and weighed on agricultural commodities from sugar to grains and oilseeds, which often track oil prices given their increasing use in making biofuels.

Limiting losses in grains, some importers have been delaying purchases in the hope any U.S.-Iran deal will push grain prices down, so there could be renewed demand if the U.S.-Iran deal holds, traders said.

Early in the session, the most-active corn Cv1 contract on the Chicago Board of Trade (CBOT) hit its weakest since August 28 at $4.06-1/4 a bushel. Wheat Wv1 hit its lowest since April 10 at $5.71 a bushel. Meanwhile, soybean futures Sv1 hit their lowest since February 6 at $11.02-1/2 a bushel and soyoil BOv1 touched the lowest price since April 29.

Still, by 9:45 a.m. CDT (1245 GMT), CBOT's most active corn contract Cv1 was up 0.48% to $4.15 a bushel, while soybeans Sv1 were up 0.02% at $11.13-3/4 a bushel and wheat Wv1 ticked up 0.04% at $5.84-3/4 a bushel.

Grain traders said they expect commodity grain markets to remain jittery this week, given that the agreement has not yet been signed and five days is a long time in the volatile Middle East. Market analysts also noted that even if the Strait of Hormuz is reopened this week, it will take time for commodity goods flows to be back to their normal pace.

"There is a big difference between opening the Strait, and restoring oil and fertilizer flows to prewar levels," Arlan Suderman, chief commodities economist at StoneX, wrote in an analyst note Monday. "Shippers remain cautious. Clearing mines in the water could take weeks to accomplish. Insurers will want to make sure that hostilities really have ended before providing affordable coverage."