By Louisa Lim BBC correspondent in Beijing

Wu Yi (right) is a tough negotiator

The agenda will include some of the most intractable Sino-US trade disputes, as well as some new arguments.

China is making headlines in the US, but in all the wrong ways.

A recent headline in the New York Times sums it up: "Looking for a villain and finding one in China".

Political weight

Many of the complaints are well-worn: for example, the US trade deficit which last year ballooned to $124bn (�68bn) and accusations that China is hoovering up manufacturing jobs from the rest of the world.

There are more tensions than people would have estimated six months ago Jim Gradoville, US Chamber of Trade

It is a measure of the political importance that trade issues are now assuming that Beijing is sending its high-profile Vice Premier Wu Yi to the US.

On Wednesday, she chairs the Joint Commission on Commerce and Trade with US secretary of Commerce Donald Evans and Trade representative Robert Zoellick.

This meeting to thrash out trade disputes is normally convened by lower-level officials.

'Trade barriers'

Alongside the old bones of contention, this year there are new sources of friction.

"There are more tensions than people would have estimated six months ago," says chairman of the US Chamber of Commerce in Beijing Jim Grandville.

China is introducing its own wireless internet standard

These new tensions include Beijing's decision to give tax rebates to domestic chip manufacturers, and its plan to impose a home-grown wireless internet standard known as "wapi" from 1 June.

Critics say these amount to thinly-disguised trade barriers.

"Wapi is an egregious example of how things should not work," says Amcham's Jim Gradoville.

It indicates there may be divisions within the Chinese government on trade issues, he says.

China boom

"A lot of questions exist about to what extent some parts of the Chinese government want to promote domestic interests over foreign ones," he said.

"Vice Premier Wu Yi may not be able to resolve these questions, but she's in a good position to raise these issues to a senior leadership level."

Wary of its increasing dependency on foreign technology, China is also introducing its own standard for DVD players, known as EVD or enhanced video discs.

These are issues which will be at the top of the American agenda, according to economist Tao Dong from Credit Suisse First Boston in Hong Kong.

"The purchasing power of the Chinese is maturing rapidly and the middle income class is exploding," he says.

"Everybody can see the market today and predict its future. The US wants a share of the market, but if it pushes too hard it could lose out."

'Grappling'

Officials in the US have indicated they are hoping for action on piracy, such as making counterfeiting a crime punishable with stiff prison sentences, rather than just fines as at present.

US firms want to expand in China

They have long called for better implementation of Chinese laws on copyright issues be implemented but lawyers here say that the onus also rests on American companies operating on the mainland.

"This is an issue that businesses from the US are grappling with on a daily basis... they believe they are losing millions and billions of dollars in intellectual property rights infringement," says lawyer Edward Lehman, who has worked in this field in China for 17 years.

"But a lot of these issues with intellectual property are frankly self-inflicted," he says.

This is because many companies do not understand how to file their patents and trademarks in China.

'Election hype'

For its part, China's wish list is likely to include asking the US to end its curbs on the import of high-tech products and to cut restrictions on Chinese exports of textile products.

Beijing is arguing that much of the noise over trade is simply election-year politics, and Edward Lehman agrees.

"I go back to the US once or twice a year and make speeches about intellectual property protection in China.

"Normally there is very little recognition of me making these speeches.

"This year we had 2-300 protestors out there saying: "Your jobs are leaving the United States and intellectual property protection isn't really taken care of".

"They didn't think the same way 365 days ago. This is election hype."

Headway

There is a clear expectation of progress at the upcoming meeting.

The US needs to show it can get results, and Beijing is aware that any lack of movement would bolster the claims of those who argue it is not playing by the rules.

The question is just how far both sides will back down and on what issues.