Swiss police on Sunday detained 32 people protesting conditions in Tibet as Chinese President Xi Jinping began a state visit in the wealthy Alpine nation.

A statement from police in the capital Bern said one protester had doused himself in flammable liquid but was stopped by security forces from setting himself alight before being taken into custody.

Xi is in Switzerland for two days of bilateral talks before heading to Davos where he will become the first Chinese president to address the World Economic Forum, an annual gathering of political, business and cultural elite.

There were an estimated 400 people, including Tibetan exiles and Swiss supporters, at the protest that had been authorised by police, the ATS news agency reported.

Some waved a banner saying "No Trade With Murderers" and demanded independence for Tibet, which Beijing says it "peacefully liberated" in 1951 and considers an inseparable part of China.

Bern police said the individuals were detained for protesting outside the agreed zone and resisted being relocated.

Xi was due to address a state dinner later Sunday alongside Swiss President Doris Leuthard.

Monday's talks will focus on topics including climate change and trade.

China is Switzerland's biggest commercial partner in Asia. In 2013, the countries inked a free-trade pact that helped boost trade volumes to 31 billion Swiss francs ($30.7 billion, 28.8 billion euros) in 2015.

But the centrepiece of Xi's visit will be his keynote address in Davos, where he is expected to preach the advent of a new world.

Donald Trump will be inaugurated as the 45th US president on the last day of the forum, a moment that many say will trigger fresh uncertainty about Washington's global leadership.

Xi's speech is expected to extol Beijing's efforts to negotiate new types of regional trade deals shorn of US influence.