US pending home sales surged to a nine-year high in April in a strong start to the prime spring season, the National Association of Realtors said Thursday.

Contracts signed for home purchases leaped a more-than-expected 3.4 percent from March, pushing the NAR pending home sales index to 112.4 the highest level since May 2006. It was the fourth straight month of gains.

Analysts on average had estimated a modest 1.0 percent rise in pending sales.

Compared with a year ago, April pending home sales were up 14.0 percent, the largest annual gain since September 2012.

All four major regions in the country saw increases last month, led by the northeast and the midwest, and price increases were accelerating in many markets, NAR said.

"Realtors are saying foot traffic remains elevated this spring despite limited -- and in some cases severe -- inventory shortages in many metro areas,"  he said. “Homeowners looking to sell this spring appear to be in the driver's seat, as there are more buyers competing for a limited number of homes available for sale."

Jim O'Sullivan, chief US economist at High Frequency Economics, said the April data added to evidence that home sales were trending higher, signaling better growth for the economy.

"Housing is an important reason why the trend in growth looks much stronger for non-manufacturing -- and the overall economy -- than for manufacturing now," O'Sullivan said.