The U.K. economy unexpectedly shrank the most since 2009 in the second quarter as record rainfall and an extra public holiday hurt output, increasing pressure on Prime Minister David Cameron to abandon the government's biggest budget squeeze since World War II.

Gross domestic product fell 0.7 percent from the first quarter, when it dropped 0.3 percent, the Office for National Statistics said in London today. Economists forecast a 0.2 percent decline, according to the median of 36 estimates in a Bloomberg News survey. Construction plunged 5.2 percent, production fell 1.3 percent and services declined 0.1 percent.

Signs of a deepening recession may add to calls for the government to do more to boost growth even after the Bank of England started a credit-easing program and increased bond purchases. The International Monetary Fund said this month that "further monetary stimulus is required" in the U.K. and the government should consider "scaling back" its fiscal tightening if growth doesn't build momentum by early 2013.