(Reuters) - British housebuilder Bellway Plc said a strong order book would help its new home output cross 10,000 units per annum for the first time, after posting a rise in first-half pretax profit on Tuesday.

Bellway said the government's 'Help to Buy' scheme continued to be an important selling tool, with home purchasers using the product in 39 percent of completions.

The scheme introduced in 2013 widened access to mortgage finance for first-time buyers in the UK unable to pay large deposits.

British housebuilders have benefited from years of rising house prices and government incentives, although the sector has been criticised for not building enough affordable housing.

"Positive trading environment, together with a substantial order book, bodes well for the full year and should enable the group to complete in excess of 10,000 new homes," Bellway said.

The company said pretax profit rose 16.6 percent to 288.7 million pounds ($405.2 million) for the six months ended Jan. 31 from a year earlier.

Average selling prices rose 7.7 percent to 275,945 pounds.

The company raised its interim dividend by 28 percent to 48 pence per share.

($1 = 0.7125 pounds)

(Reporting by Radhika Rukmangadhan in Bengaluru; Editing by Gopakumar Warrier)