U.N. sees world growth rising in 2017, threats from Trump and Brexit

GENEVA (Reuters) - Global economic growth will quicken to 2.7 percent this year and 2.9 percent in 2018, after growing by 2.2 percent in 2016, the United Nations said in its annual economic forecast on Tuesday.

However it saw uncertainty created by Britain's vote to leave the European Union, and British growth is expected to slump from an estimated 2.0 percent in 2016 to 1.1 percent in 2017 and 1.3 percent in 2018.

Tax policies espoused by U.S. president elect Donald Trump could also have adverse effects on the world economy, said Alfredo Calcagno, head of macroeconomic and development policies at the U.N. economic agency UNCTAD.

"This might generate a deficit in the short run… and that could bring us towards a challenge for the global economy," he told a news conference in Geneva. "The other element of tax reform… is whether this tax system would mean a kind of higher protection for American producers. Then this would incorporate a huge challenge for the multilateral system and the WTO."

(Reporting by Tom Miles; Editing by Dominic Evans)