Flour millers and food retailers are watching closely to see if their wholesale food bills will go up as demand for Australian wheat increases because of a freeze on Russian exports.

But grain traders maintain there will be zero effect on bread prices.

Australian wheat farmers have been buoyed by a $100-a-tonne spike in the value of their crops this year, which will be harvested in the next three months.

Wheat prices were $297 a tonne yesterday, much greater than the $223 of 12 months ago and a $178 low in April this year, according to grain trade analyst Malcolm Bartholomaeus.

Australian wheat values will remain strong after Russian Prime Minister Vladimir Putin banned all wheat exports a month ago because of the worst drought in his nation's history.

Fiona Fleming, corporate affairs manager with George Weston Foods, a major Australian flour miller, was uncommitted on whether flour costs would rise as more home-grown wheat travelled to foreign countries.

She said the increase in the worldwide price of wheat was unprecedented and ''will obviously have a flow on impact'' on domestic wheat prices.

The general manager of the National Baking Industry Association Paul McDonald expected bakery prices to be unchanged at least until the Australian wheat harvest at the end of the year.

''We will start to see the impact come November and December,'' Mr McDonald said.

Mr Hoitink, who owns bakeries at Chapman and Yarralumla, said wholesale food prices had been favourable in recent times.

''It would not be good if more Australian wheat was exported and we were penalised,'' Mr Hoitink said.

Working in Mr Hoitink's favour will be the large 2010 wheat crop of 22 million tonnes, according to Australian Crop Forecasters.

For more on this story, including comments from grain traders on the potential impact of wheat prices on the cost of bread, see the print edition of today's Canberra Times.