US producers raised doubts over the prompt resumption of trade after Russia's relaxation of a ban on imports of US poultry, cutting hopes of clearing rising inventories.

Gennady Onishchenko, the head of Russia's consumer protection watchdog, said that supplies of US poultry to what was its biggest export market last year "may restart in 1.5-to-two months, in the best case".

The comments disappointed investors after a deal between US president Barack Obama and his Russian counterpart, Dmitry Medvedev, last week had appeared to clear the way to a speedy resolution of the trade curbs, which Russia introduced earlier this year.

Russia, which is attempting to build up its domestic chicken and hog businesses, said that a chlorine-based cleaning rinse used by US producers broke its food safety rules.

Exports to Russia may not resume as quickly as people had believed, analysts said, noting that this would be negative factor for the range of protein markets.

Delayed sales of chicken to Russia would leave more in the US to compete with supplies of beef and pork. Earlier this month, official data showed the level of chicken products in US cold stores at 132.16 million pounds, 89% higher than a year before.