The United States will retain unchallengeable global dominance for at least two decades, a top Chinese official has said in an essay urging his government to find a balance between assertion and restraint.

Le Yucheng, director-general of policy planning for China's Ministry of Foreign Affairs, made the remarks before Chinese President Hu Jintao's visit to the United States last week, but they reflect the thinking behind Hu's four-day effort to both reassure Washington while pressing Beijing's own complaints.

The worst of the global financial crisis had passed, but its aftershocks would continue to drag on wealthy economies, and are hastening a historic transformation in the international balance of powers, Le said in the Foreign Affairs Review, a Chinese-language publication overseen by his ministry.

China must not assume, however, that the United States is suffering irreversible decline or that the two powers will soon be near equals, Le said in an issue that reached subscribers on Monday but was dated late December.

With the newly emerging powers growing faster, the United States' share of the pie is shrinking in relative terms, and so the fact is that its advantages are also shrinking, said Le.

But the United States is after all the United States. It makes up one quarter of the world economy, it holds incomparable military, scientific and innovative strengths, and we must not underestimate the United States' capacity to adjust and restore its powers, said Le.

In particular, the United States' strength and influence remain far in the lead, and will be unbeatable for the next 20 to 30 years.

President Hu told President Barack Obama and U.S. lawmakers last week that China was no threat to the United States, and that its growth was a boon to U.S. companies and workers.

Some of Le's comments were published in a Chinese newspaper, the Global Times, late last year, and the Foreign Affairs Review said his essay also took elements from his recent official reports on international developments.

UNEQUAL TREATMENT

Le stressed that while China was a rising power, it did not want to cast itself as an emerging peer or challenger of the United States and advanced West. New comments from the Chinese Foreign Minister also underscored that theme.

The international situation is undergoing far-reaching adjustments in the wake of the financial crisis, Foreign Minister Yang Jiechi wrote in International Studies, a Chinese-language journal that also reached subscribers on Monday.

But developing countries still face many hardships and challenges, he wrote.

In 2010, China struggled with a succession of international quarrels -- over U.S. arms sales to Taiwan, a territorial dispute with Japan, and over North Korea and U.S. military exercises -- that stirred foreign officials and analysts to warn that Beijing was becoming more hardline.

Le dismissed those warnings but said that China would not be pushed around.

While we stress keeping our heads down and working hard, not taking the lead or becoming the banner-holder, that does not mean that China will meekly submit to pressure, tolerate being bullied or stay passive, he said.

In bilateral cooperation with the United States, China feels that it receives unequal treatment from the U.S. on many points.

In past months, the United States and South Korea held joint military exercises to warn North Korea, which had alarmed the region by shelling a South Korean island in disputed waters and by claiming advances in uranium enrichment, which could give it a second pat to making nuclear weapons.

Le said military exercises would not solve the long-standing conflict between North and South Korea. But China was not seeking to push the United States from the region, he said.

In fact, China has never wanted to divide up the scope of our powers and we don't have the intention or the strength to push out the United States.

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