Central London values fell by 3.8% on the month, MSCI said on its website.
Expectations of a sharper fall in property values led retail investors to flee UK property funds last month after Britain voted to leave the European Union, causing as much as 18 billion pounds ($23.24 billion) in property fund investments to be frozen.
MSCI said on the final index results were delayed due to a technical failure.
($1 = 0.7744 pounds) (Editing by Rachel Armstrong)
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