By Jennifer Hill

LONDON (Reuters) - House price growth in prime central London is cooling, but should remain in double figures next year, a report says.

Uncertainty in financial markets tempered property price growth in the prime central London market in August, according to estate agent Knight Frank.

Its index charts the value of flats and penthouses with an average value of over 1.5 million pounds and houses with an average value of close to 3 million pounds.

The monthly growth rate fell to 2.1 percent in August from 3.9 percent in July.

However, prices have risen by 37.9 percent in the year to end-August, the data shows.

Knight Frank predicted that the annual figure would drop to 30 percent by the end of 2007 -- much in line with the 29 percent recorded during the calendar year 2006.

But it anticipated much more moderate growth next year, forecasting that the price of prime property in central London will rise by 10 percent in 2008.

Growth will be led by the super prime market of 5 million pound-plus properties and the sub-1 million pound market, where there is a degree of "catch up" beginning to take place, it said.