LONDON - House prices nudged up last month, beating expectations for no change, driven by sales in more affluent areas, data from mortgage lender Nationwide showed on Tuesday.

House prices rose 0.4 percent in October having risen 0.1 percent in September, pushing them 0.8 percent higher than a year ago, the first time annual house price growth has been in positive territory for six months, Nationwide said.

Given the challenging economic backdrop, October's data is encouraging, but it doesn't fundamentally change the picture of a housing market that is treading water, said Robert Gardner, chief economist at Nationwide.

Data released on Monday showed a slowdown in mortgage lending with approvals of home loans -- a gauge of house prices six months down the line -- and net mortgage lending weakening in September, pointing to a further softening in the housing market.