UPDATE 3-In Davos, Xi makes case for Chinese leadership role

(Removes quote attributed wrongly to John Kerry)

* Xi warns against trade war in apparent message to Trump

* He is first Chinese president to appear at WEF

* Appearance comes amid rising tensions with Trump team

* China economy worries ease but big risks remain

By Noah Barkin and Elizabeth Piper

DAVOS, Switzerland, Jan 17 (Reuters) - Chinese President Xi Jinping offered a vigorous defence of free trade at the World Economic Forum in Davos on Tuesday in a speech that underscored Beijing's desire to play a greater global role as the United States turns inward.

In the first appearance by a Chinese leader at the annual meeting of political leaders, CEOs and bankers in the Swiss Alps, Xi also cautioned other countries against blindly pursuing their national interests, in an apparent reference to the "America first" policies of Donald Trump.

Real estate mogul and former reality TV star Trump, who will be inaugurated as U.S. president on Friday, campaigned on a promise to confront China more aggressively on trade.

He has vowed to renegotiate or ditch multilateral trade agreements and protect U.S. industries from foreign competition by levying new tariffs on goods from abroad.

Xi likened protectionism to "locking oneself in a dark room" in the hopes of protecting oneself from danger, but in so doing, cutting off all "light and air".

"No one will emerge as a winner in a trade war," Xi said in a nearly hour-long speech in a massive conference hall as U.S. Vice President Joe Biden looked on.

He said Beijing would not boost its trade competitiveness by devaluing its currency, something Trump has repeatedly said China has done in the past, and urged all signatories of a landmark climate deal in Paris last year to stick to the agreement.

Trump has criticised the deal and indicated he may pull the United States out of it.

LEADERSHIP VACUUM

As Trump vows to focus on American interests, Europe is increasingly pre-occupied with its own troubles, from Brexit and militant attacks to the string of elections this year in which anti-globalisation populists could score gains.

This has left a vacuum that China seems eager to fill.

More than half a dozen senior Chinese government figures joined Xi in travelling to Davos, whereas in prior years Beijing sent fewer, lower-level officials.

A large number of sessions at the WEF are focused on Asia this year, including one entitled "Asia Takes the Lead".

"In a world marked by great uncertainty and volatility the world is looking to China," WEF founder and chairman Klaus Schwab said before welcoming Xi to the stage.