CANBERRA: US corn futures fell for the first time in seven sessions on Tuesday, weighed by a stronger US dollar, although strong demand for supplies kept prices near a more than a seven-year high.

Soybeans edged lower despite concerns over crops in South America, while wheat was little changed.

The most active corn futures on the Chicago Board Of Trade were down 0.2% at $5.48 a bushel by 0354 GMT. Corn rose 0.4% on Monday, when prices hit a June 2013 high of $5.54 a bushel.

Analysts said a stronger dollar was denting prices, but losses were limited by strong demand, particularly from China.

"Market chatter about China's appetite for feed grain is headed into overdrive," said Tobin Gorey, director of agricultural strategy, Commonwealth Bank of Australia.

The US Agriculture Department confirmed private export sales of 125,730 tonnes of US corn to Mexico and another 110,000 tonnes to Japan on Monday morning, for delivery in the 2020/21 marketing year.

That was on top of corn sales last week to China totalling 3.74 million tonnes, one of the largest US corn export sales weeks on record.

The most active soybean futures were down 0.1% at $13.64-1/2 a bushel, having closed down 0.3% on Monday.

The most active wheat futures were little changed at $6.50-1/2 a bushel, having closed down 1.8% on Monday.

Wheat continues to shake off the prospect of tighter global supplies.

Russia, one of the world's largest wheat exporters, is considering a formula-based tax on the wheat it sends abroad from June 1, a month earlier than previously stated, two sources familiar with government talks told Reuters on Saturday.