CHICAGO, May 6 (Reuters) - Chicago Board of Trade soybean futures tumbled on Wednesday, giving up recent gains, as a decline in crude oil prices caused a flurry of long liquidation by managed commodity funds that had recently taken massive long positions on grains.

• Oil prices fell sharply to two-week lows on Wednesday as optimism grew about a possible end to the war in the Middle East, with reports the United States and Iran were nearing an initial peace deal. O/R

• A source from mediator Pakistan said the United States and Iran were closing in on an agreement on a one-page memorandum of understanding.

• The American Soybean Association said it was worried China, the world's largest soy importer, could reimpose higher tariffs on American soybeans in response to a U.S. trade investigation into excess industrial capacity in major trading partners.

• Traders were waiting for a meeting between U.S. President Donald Trump and Chinese leader Xi Jinping next week, though many expect the world's largest soybean importer to purchase only minimal quantities of U.S. soybeans, if any at all.

• Brazil's soybean area is expected to post only marginal growth in the 2026/27 season due to higher production costs and risks linked to the El Nino climate phenomenon, Argus analyst Nathalia Giannetti said on Wednesday.

• CBOT July soybeans SN26 fell 16-3/4 cents to end at $11.94-3/4 per bushel.

• CBOT May soyoil BON26 fell 1.89 cents to end at 75.02 cents per pound.

• CBOT May soymeal SMN26 fell $3.10 to $317.30 per short ton.