House prices in Britain rose by 8.4 percent last year with London posing the strongest annual growth of nearly 15 percent, said the mortgage lender Nationwide Building Society on Friday. In its monthly house price index report, Nationwide said the house prices continued to gain momentum as 2013 drew to a close with the price posing a monthly rise of 1.4 percent in December, bringing the average house price up to 175,826 pounds (288,601 U.S. dollars) from 174,566 pounds in November. House price growth kept on rising in London, with the growth at 14.9 percent year on year, the highest growth rate since the first quarter of 2010. However, despite the strong growth last year, house prices in Britain are still around 5 percent below 2007 peak. "The UK housing market followed the trajectory of the wider economy through 2013, gaining momentum as the year progressed," said Robert Gardner, Nationwide's chief economist. "A large part of the pickup in the housing market can be attributed to further improvements in the labour market and the brighter economic outlook, which helped to bolster sentiment amongst potential buyers. "Policy measures also played an important supporting role by helping to keep mortgage rates close to all-time lows and improving the availability of credit, especially for those with smaller deposits," he said. According to the Nationwide, house price growth picks up across all regions of the country in 2013, with London's house price as the most expensive one. The average price in London hit 345,186 pounds in the last quarter of 2013, rising 4.7 percent over the previous quarter. The house prices in London are now 14 percent above the 2007 peak, said the Nationwide. Meanwhile, North Ireland remained the weakest performing region with the average house price stood at 111,612 pounds in the last quarter of 2013, posing a quarterly growth of 3.9 percent and annual growth of 7.0 percent. The prices in North Ireland are still around half the level prevailing in late 2007.