WASHINGTON - As President Obama prepares to go to Northern Ireland today to promote a new trade pact with the European Union, hopes are running high for many U.S. businesses eager to squeeze more cash from one of the world's most lucrative markets.

For poultry growers, it's a chance to end a ban on chickens disinfected using chlorine, a widely accepted cleaning practice in the United States.

For the confectionary industry, it's a way to get rid of labeling requirements to disclose whether candy, gum or chocolates contain any genetically modified ingredients.

And for Errico Auricchio, a Wisconsin cheese maker, it could help sell his Romano cheese throughout Europe, even though it's not manufactured in the Italian city for which it's named.

With Europeans' longstanding suspicions of American food, Obama faces an uphill climb in his bid to revise trading rules between the two giants.

The stakes are high for the president, who wants to double U.S. exports under his watch and whose team has made a European deal a top economic plank of his second term.

But in both Europe and the United States there's skepticism, with many saying the historical hurdles and huge cultural differences will be hard to overcome.

"This negotiation will be far more difficult than a lot of people have anticipated," said Clayton Yeutter, the U.S. trade representative from 1985 to 1988, before becoming the secretary of agriculture.

Business officials are counting on the president to carry their message at the G-8 Summit in Northern Ireland, which opens Monday, and in Berlin on Wednesday, when he is scheduled to give a speech at the Brandenburg Gate and to meet with German Chancellor Angela Merkel.

"I hope he understands the gravity of the situation," said Auricchio, who moved to the United States from Italy in 1979 and now runs his 550-employee business in Green Bay.

Many U.S. business officials say the timing for a deal could be perfect. They argue that a struggling economy has made Europeans hungry for more trade and more likely to ease onerous food-safety rules.

Some are braced for the worst, fearing a new pact could lead to lower standards in both Europe and the United States.

"We think there's a lose-lose situation with consumers on both sides of the Atlantic," said Tony Corbo, senior lobbyist for the U.S. consumer group Food and Water Watch. He noted that unlike the United States, the European Union has not yet passed zero-tolerance standards for some dangerous types of e-coli, Listeria and other food toxins.

But Yeutter, who called the trade pact "an awesome opportunity" for both sides, said that the Europeans have done much "backpedaling" since the talks were announced in February, raising questions of how serious they are in tackling a deal. While U.S. officials say they want to negotiate all issues, a new fact sheet produced by the European Commission says that "tough EU laws" aimed at protecting human life and health "will not be part of the negotiations."

If an agreement emerges, Yeutter said, the Obama administration will need to make sure that it has solid backing from U.S. farm groups.

"It's difficult to get trade agreements of any kind through the U.S. Congress these days, and you certainly cannot do it without the support of American agriculture," Yeutter said. "Some of these differences are going to have to be bridged."