European stocks advanced, posting the biggest four-day rally since April, after the International Monetary Fund said it will raise its U.S. growth outlook.

The Stoxx Europe 600 Index climbed 0.7 percent to 323.40 at the close of trading in London. The gauge has rallied 16 percent this year, including the 3.9 percent gain in the past four days. The Stoxx 600 is heading for its biggest annual jump since 2009.

European stocks rose 3.7 percent last week, the biggest rally since April, after the Federal Reserve’s decision to reduce its monthly bond purchases increased investors’ confidence in the strength of the U.S. economic recovery.

The IMF will increase its outlook for the U.S. economy as a budget deal and falling unemployment ease doubts about the future, Managing Director Christine Lagarde said in an interview yesterday on NBC’s “Meet the Press.” The IMF said in October the world’s largest economy would expand 2.6 percent next year. Lagarde didn’t specify new figures. The Washington-based fund usually issues projections in January.

A U.S. report showed the the Thomson Reuters/University of Michigan final index of consumer sentiment climbed to 82.5 in December from 75.1 a month earlier. The median forecast of 61 economists in a Bloomberg survey called for 83 after a preliminary reading of 82.5. Consumer spending rose in November by the most in five months, according to a separate report.

National benchmark indexes advanced in 14 of the 18 western-European markets today. France’s CAC 40 added 0.5 percent and Germany’s DAX rose 0.9 percent. The U.K.’s FTSE 100 climbed 1.1 percent.

ARM Holdings increased 3.9 percent to 1,110 pence after Apple’s agreement with China Mobile. Dialog Semiconductor Plc, which got 77 percent of its revenue from the iPhone maker, rose 3.4 percent to 15.68 euros.

Lanxess advanced 4.4 percent to 47.74 euros. CEO Axel Heitmann told Frankfurter Allgemeine Sonntagszeitung that the company will reach its goal of 710 million euro ($972 million) to 760 million euro in earnings before interest, tax, depreciation and amortization before special items, adding he is confident about improving results in 2014.

Orell Fuessli declined 2.2 percent to 88 Swiss francs after saying it will report an operating loss of 20 million francs ($22.3 million) for 2013. It cited special charges at its security-printing unit, which produces Switzerland’s banknotes. On Oct. 1, the company said it was liable for losses incurred by customers in relation to banknotes stolen during production.