DAVOS (DPA) - Three thousand politicians and managers kick off their annual meeting in the Swiss resort of Davos on Tuesday (Jan 22), discussing solutions to global challenges despite the absence of some of the world's key leaders.

Brazil's new far-right President Jair Bolsonaro will hold the first keynote speech of the four-day World Economic Forum annual meeting in the snowy mountains in the afternoon.

It is Bolsonaro's first international appearance since he was sworn in as president at the start of January. Although the controversial populist leader has already announced a plan to privatise infrastructure, it is still unclear whether he will really opt for ultra-liberal economic policies.

The Brazilian president takes the forum's keynote slot from US President Donald Trump, who cancelled his attendance to deal address a weeks-long partial government shutdown.

British Prime Minister Theresa May and French President Emmanuel Macron are also forgoing Davos this year, opting instead to address political crises at home.

Their absences are likely to place the focus on attendees such as German Chancellor Angela Merkel, Japanese Prime Minister Shinzo Abe or UN Secretary General Antonio Guterres.

Slowing global economic growth, populism, political tensions, trade wars and Britain's unclear path out of the European Union are among the main worries of the world's leaders, according to surveys and forecast published ahead of the Davos meeting.

This year's official theme is Globalisation 4.0: Shaping A New Architecture In The Age Of The Fourth Industrial Revolution - a vision of an interconnected world that tackles the economic inequality that goes along with globalised trade and production.