By Laura MacInnis and William Schomberg
GENEVA (Reuters) - Global trade talks began a third day onWednesday after emerging economies such as Brazil and SouthAfrica said a U.S. offer to cut its farm subsidies was not tojustify reciprocal moves by them.
Without a breakthrough in the coming days, the World TradeOrganisation's Doha negotiations risk further years of delay.
On Tuesday, the United States said it was ready to cut itsannual ceiling on trade-distorting farm subsidies to $15billion (7.5 billion pounds) -- a level lower than its spendingin seven of the last 10 years -- in order to kick-start thetalks.
But India, Brazil and other big developing countries saidWashington had to make deeper cuts before they would offerconcessions of their own because the ceiling representedvirtually double the level of U.S. farm subsidies last year.
"Within what is politically viable, $13 (billion) is closeto reasonable," Brazilian Foreign Minister Celso Amorim said.
Kent Conrad, a Democratic senator from grain producer NorthDakota, expressed concern that subsidies would be capped.
He said U.S. trade chief Susan Schwab appeared "to benegotiating against herself. She's certainly not negotiating inthe interests of hard-working family farmers in North Dakotaand elsewhere in the country".
Officials said talks on getting developing countries toopen up their markets in manufactured goods were heated andtrade officials said they were extending hotel reservationsinto next week with talks likely go beyond Saturday's plannedend date.
Without a breakthrough on the core issue of farm andmanufacturing trade by the August summer break, the Doha roundrisks being put on hold by the U.S. presidential elections andcould remain that way for a couple of years.
Billed as a chance to bolster the global economy and helpfight poverty, the round has struggled from crisis to crisissince it was launched in 2001.
Some supporters say its conclusion this year would stillsend a signal against protectionism as economies slow.
Schwab said Washington's offer on subsidies on Tuesday was"a major move" and developing countries now had to follow suitby opening up their economies and farm markets to more imports.
Developing countries complain that huge U.S. subsidiessqueeze their farmers out of the market, reducing food suppliesand contributing to a recent spike in global food prices. TheEuropean Union also faces calls to cut its farm import tariffs.
(Writing by William Schomberg; Editing by Stephen Weeks)