GENEVA - Nations should strive for a world where nuclear weapons are prohibited and where existing stocks are destroyed, Chinese President Xi Jinping said in a speech at the United Nations on Wednesday.

"Nuclear weapons should be completely prohibited and destroyed over time to make the world free of nuclear weapons," the Chinese president said in Geneva.

In a lengthy address at the UN's European headquarters alongside with the world body's new chief Antonio Guterres, Xi also made a robust case for a global governance system based on equality among nations.

"We should reject dominance by just one or several countries", Xi said, adding that "major powers should respect each other's core interests."

"Big countries should treat smaller countries as equals instead of acting as a hegemon imposing their will on others," he further said.

In his disarmament call and plea for sovereign equality Xi offered China as a nation "committed to building a world of lasting peace."

The remarks come at the end of a four-day diplomatic tour across Switzerland that included a landmark address at the ongoing World Economic Forum in Davos. Some analysts saw his Davos speech on Tuesday as a attempt to grab the mantle of global leadership from the United States, where Donald Trump will be sworn in as the country's 45th president on Friday.

Trump's astonishing rise has raised questions among political elite about Washington's role in the world.

Trump, a political novice, has offered a series of at times contradictory remarks on American nuclear power, saying the country needed to "greatly strengthen and expand its nuclear capacity", while later indicating he favoured a disarmament deal with Russia.

The world needs China and the United States to have a stable and cooperative relationship, Chinese President Xi Jinping told US Vice President Joe Biden, just days before new uncertainy looms with Donald Trump taking office as president.

Meeting on the sidelines of the World Economic Forum in Davos, Xi told Biden that he "positively appraised" his efforts to increase friendship and mutual understanding between the two countries, China's Foreign Ministry said late on Tuesday.

"In the 38 years since the establishment of diplomatic relations, relations between the two countries have weathered wind and rain, but generally have continued to forge ahead," the statement paraphrased Xi as saying. Under President Barack Obama, there has been a "correct" development in relations, and important and positive results achieved, with trade and people-to-people exchanges reaching new highs, Xi added.

"The basic interests of the people of both countries and the world need China and the United States to work hard, to form a long-term, stable cooperative relationship," Xi said.

The statement cited Biden as saying that the United States hopes the two countries can continue to deepen mutual trust and expand cooperation.

It made no mention of Trump, though China's top diplomat, State Councillor Yang Jiechi, who last month met a senior advisor to Trump, also attended the Xi-Biden meeting, the foreign ministry said.

Trump, who takes office on Friday, has rattled Beijing with threats to impose tariffs on Chinese imports and by questioning the United States' commitment to the "one China" policy, under which Washington acknowledges China's position that Taiwan is part of its territory.

The United States should not allow a delegation from Taiwan to attend US President-elect Donald Trump's inauguration, China's Foreign Ministry said on Wednesday, raising a new bone of contention in Beijing's relations with the incoming government.

Trump broke with decades of precedent last month by taking a congratulatory telephone call from Taiwan President Tsai Ing-wen, and he has also said the "One China" policy was up for negotiation, a position Beijing strongly rejected.

A Taiwan delegation, led by former premier and ex-ruling party leader Yu Shyi-kun, and including a Taiwan national security adviser and some lawmakers, will attend Friday's inauguration, Taiwan's Foreign Ministry said this week.

It is typical for Taiwan to send a delegation to US presidential inaugurations.

A spokesman for Taiwan President Tsai Ing-wen's office said no meetings were scheduled with the new Trump administration while the delegation was there for the event.

China considers Taiwan a breakaway province, with no right to have any kind of diplomatic relations with other countries.

Chinese Foreign Ministry spokeswoman Hua Chunying said China was opposed to Taiwan using any excuse to send people to the United States to "engage in activities to interfere in or damage China-US ties".

"We again urge the relevant side in the United States not to allow the Taiwan authority to send a so-called delegation to the United States to attend the presidential inauguration and not have any form of official contact with Taiwan," Hua told a regular news briefing.

"China's position has already accurately and unmistakably been given to the US administration and Trump's team."

China's ambassador to the United States, Cui Tiankai, will attend the inauguration on its behalf, she added.

Defeated Nationalist forces fled to Taiwan in 1949 after losing a civil war with the Communists.

China has never renounced the use of force to bring Taiwan under its control, and proudly democratic Taiwan has shown no interest in wanting to be run by Beijing.

China is deeply suspicious of Taiwan's Tsai, whom it suspects of wanting to push for the island's formal independence, a red line for China.

Tsai, who visited the US this month while travelling to and from Central America, says she wants to maintain peace with China.

The administration of President Barack Obama has repeatedly reinforced the US commitment to the "one China" policy, under which Washington acknowledges China's position of sovereignty over Taiwan, since Trump's call with the Taiwanese leader.

Trump is to be sworn into office on Friday.