British house prices dropped by 0.2 percent in September, the first month-on-month fall since April 2013.
The annual pace of house price growth also moderated to 9.4 percent from 11 percent in August, according to the data released on Tuesday by the Nationwide, one of Britain's largest mortgage lenders.
London experienced the largest deceleration, although at 21 percent year-on-year it is still leading the rest of the country by some margin.
It provided further evidence of a cooling housing market, said Matthew Pointon, Property Economist of the Capital Economics.
"Buyers have been discouraged by house prices which are very high compared to earnings, concerns over future interest rate rises and a lack of homes up for sale. That has led to a sharp reduction in the mismatch between active demand and supply, and accordingly it is no longer a seller's market," Matthew said.
Robert Gardner, Nationwide's Chief Economist, said that the outlook of British housing market remained uncertain.
"There have been tentative signs from surveyors and estate agents that buyer demand may be starting to moderate, but the low level of interest rates and strong labour market suggest that underlying demand is likely to remain robust," Robert said.