China's likely next leader Xi Jinping warned the United States against plans to boost its military strength in Asia as he prepared for a closely watched visit to Washington starting Monday.

China's vice president, who is tipped to rule the rising Asian power until 2023, called on the United States to prioritize economic growth and promised anew that Beijing would address foreign concerns about its currency's value.

In a written interview with The Washington Post, Xi said the Pacific Ocean had "ample space" for both China and the United States but insisted that Asian countries were concerned foremost with "economic prosperity."

"At a time when people long for peace, stability and development, to deliberately give prominence to the military security agenda, scale up military deployment and strengthen military alliances is not really what most countries in the region hope to see," Xi said.

"We welcome a constructive role by the United States in promoting peace, stability and prosperity in the region. We also hope that the United States will fully respect and accommodate the major interests and legitimate concerns of Asia-Pacific countries," he said.

US President Barack Obama, while seeking to trim vast military spending in response to budget pressure, has vowed to boost power in Asia where a number of nations have voiced concern at what they charge is a more assertive China.

The United States has moved in recent months to send troops to Australia and the Philippines. It has also sought to increase military ties with Vietnam and Singapore, while maintaining longstanding bases in Japan and South Korea.

On Monday, Chinese foreign ministry spokesman Liu Weimin emphasised the importance of trust between the two countries.

"We always believe that the two countries are not rivals but cooperation partners," he told reporters, after Xi left Beijing for the United States.

"China is committed to the road of peaceful development. China's development is an opportunity for the US and other countries, instead of a threat."

The Obama administration has tried to build personal bonds with Xi in hopes of future cooperation. China starts its power transition later this year, with Xi widely expected to succeed President Hu Jintao in 2013.

Xi arrives Monday and will enjoy a welcome Tuesday at the White House, including a meeting with Obama. He will also stop at the Pentagon for talks billed by US officials as significant in building military trust.

Xi will Wednesday visit Iowa -- where he paid a formative first visit to the United States in 1985 as a low-ranking official -- and Los Angeles.

White House officials have said that they want a positive relationship with Xi but that they will press key US concerns, some of which may grow in prominence as November elections approach.

US lawmakers accuse China of devastating US industry by keeping its renminbi currency artificially low to boost imports and of failing to protect the intellectual property of US companies.

Xi said that Americans have benefited from China's rapid economic growth. Repeating a figure offered by Hu on a state visit to Washington last year, Xi said that US consumers have saved $600 billion by buying Chinese goods.

"We have taken active steps to meet legitimate US concerns over IPR (intellectual property rights) protection and trade imbalance, and we will continue to do so," Xi said.

"We will continue to press ahead with the reform of the RMB (renminbi) exchange rate formation mechanism and offer foreign investors a fair, rule-based and transparent investment environment," Xi said.

But Xi also repeated calls for the United States to ease restrictions on exports of sensitive technology to China and to "provide a level playing field" for Chinese businesses in the US market.

China has let its yuan appreciate since 2010 -- largely in response to inflation concerns.

Michael Froman, a White House deputy national security adviser, on Friday cited progress on the currency valuation and other economic issues but said that "there's a lot more to be done."

The United States has said it will also voice concern about human rights in China, amid a clampdown on domestic dissent and Tibetan areas, along with China's recent veto with Russia of a UN Security Council resolution that would have pressured Syrian President Bashar al-Assad over escalating violence.