This monthly increase means an annual growth rate of 32 per cent, the estate agent claims.
Flats and penthouses from selected London areas worth more than £1.5 million and houses valued in excess of £3 million are included in Knight Frank's monthly study.
"Among the best performing areas are Chelsea and St John's Wood, where both houses and flats have been performing strongly," commented the firm's head of residential research, Liam Bailey.
He explained that massive supply shortages and overseas demand were driving the growth, with the number of available properties falling by 27 per cent in March.
"As City bonus money filters out of the market, continued strong price performance can be explained by supply shortages and ongoing international demand," Mr Bailey continued.
Prices on Knight Frank's prime central London index have now increased for 27 consecutive months.
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