WASHINGTON – Europeans can be downright fussy when it comes to their food.

Many of them think, for example, that only the rich, hard cheese that has been made for hundreds of years in the Parma region of Italy should be labeled as Parmesan — not the stuff made by Kraft Foods or others.

And despite repeated assurances from the United States, many of them have questioned whether it's really safe to eat meat injected with hormones or the genetically modified crops that Americans gobble up.

Food issues could be among the trickiest to overcome as U.S. negotiators aim to expand trade with the European Union, moving on a plan announced Tuesday night by President Obama in his State of the Union speech.

Obama said he wanted the United States to approve a comprehensive deal with the European Union "because trade that is free and fair across the Atlantic supports millions of good-paying American jobs."

And while trade deals with poorer countries often force U.S. negotiators to try to raise others' standards for labor, the environment and food safety, the shoe could be on the other foot this time around.

On Wednesday, administration officials acknowledged that they'll be forced to confront a host of sensitive issues as they seek to wrap up a new deal by the end of 2014.

But they said the payoff could be huge, with millions of jobs at stake.

"This is potentially a very big deal," said Michael Froman, Obama's deputy national security adviser for international economics.

In a conference call with reporters, Froman said that the United States and the European Union already account for one-third of the total trade in goods and services around the world and that 13 million jobs already exist because of the trade relationship between the two.

He said those numbers could grow substantially and that "the stars could well be aligned … to resolve issues that have been difficult to resolve before."

And he said that agriculture issues, despite their difficulty, will be a central part of the negotiations.

"Nobody should be under any impression that we are not going to be resolving agricultural issues," said Froman.

No one's expecting it to be easy.

Differing tariffs and government subsidies on farm goods are sure to yield even more fights.

"The negotiations will be a hard slog, particularly in the agriculture sector, but the resulting billions of dollars in increased exports will be worth the effort," said Bill Frymoyer, a senior adviser and trade expert at the Washington law firm Stewart and Stewart. His experience dates to the early 1990s, when he worked on the North American Free Trade Agreement as a top aide to then-House Democratic leader Dick Gephardt.

In his speech to Congress, Obama made it clear that he intends to continue his push to increase U.S. exports during his second term.