European Council President Donald Tusk addresses a news conference following a European Union leaders summit in Brussels December 18, 2014. [Photo/Agencies]

BRUSSELS - In a striking symbol of changed leadership, European Union leaders wrapped up their last summit of the year a day early after agreeing to launch an investment fund and maintain sanctions on Russia over Ukraine.

New European Council President Donald Tusk, chairing his first summit, made a point of keeping the meeting short and political, without the customary wrangling over the wording of a rambling final statement, known in EU jargon as "conclusions".

"European Council finished. On time," the former Polish prime minister tweeted after the 28 leaders ended about 8 hours of discussion. EU officials said it was the first time in memory that a two-day summit had been cut short in this way.

The 2-1/2 page broad statement compared with up to 40 pages of detailed policy conclusions at previous summits, when leaders would negotiate for hours over a handful of phrases. The last EU summit conclusions in October ran to 15 pages.

Tusk has imposed a new, more informal and political style since taking over on Dec 1 from former Belgian premier Herman Van Rompuy, who was used to marathon coalition negotiations.

Aides said Tusk wanted heads of state and government to focus on their original mission of giving strategic guidance to the EU rather than haggling over up to a dozen detailed policy issues from carbon emissions quotas to budget rebates.

Unlike Van Rompuy, he set out his own views on the short summit agenda to reporters on his way into the meeting.

Sceptics said the summit agenda was unusually thin, with no substantial issues of money or power at stake. Whether Tusk's resolution will stand the test of a crisis remains to be seen.

But his style won at least one important fan. German Chancellor Angela Merkel told reporters: "Personally I felt very comfortable with the new Council president.

"And we even finished before midnight."