SEOUL, April 17 (Reuters) - South Korea's house prices contracted for the 10th straight month in March, but with the pace softening to the slowest in five months, data showed on Monday.

The nationwide house price index fell 0.78% in March from the previous month, slower than 1.15% in February and the slowest since October, according to the Korea Real Estate Board.

The pace of decline slowed for a third consecutive month, after hitting 1.98% in December, which was the steepest on record since the data series began in late 2003.

The board said the pace eased in March due to a decrease in urgent sales and optimism over deregulation in the greater area of the capital Seoul.

South Korea's house prices have been falling for every month since June last year due to the central bank's aggressive interest rate hikes. The government, meanwhile, is trying to avert a hard landing, such as loosening financial regulations for homebuyers. (Reporting by Jihoon Lee; Editing by Jacqueline Wong)