Monthly net retail sales were negative in August for the first time since 2016's EU referendum with £217m of outflows, according to data from the Investment Association.
European and UK equities were worst affected by negative sentiment, which meant total funds under management for the IA universe remained flat
UK equity funds, which combine the IA UK All Companies, UK Equity Income and UK Smaller Companies sectors, saw outflows of £429m, up from £315m of outflows in July.
The UK All Companies sector was the worst-selling sector overall, with outflows of £355.8m.
European equities was also out of favour with £303m of redemptions, nearly double the £156m outflows reported in July.
Instead, investors were favouring global and multi-asset funds with Global, Mixed Investment 40%-85% Shares and 20%-60% Shares sectors among the best-selling sectors.
Global was at the top of the table, unchanged from July, with sales rising from £397m to £416.6m.
This was followed by Mixed Investment 40%-85% Shares with net retail sales of £304.1m and the Volatility Managed sector, which was launched last year, which saw retail inflows of £183.5m.
Chris Cummings, chief executive of the Investment Association, said: "The uncertainty in the Brexit negotiations continued to be a key factor denting investor confidence in August, with funds experiencing the first retail outflows since the EU referendum result.
"UK equities remain firmly out of favour, with European equities also experiencing another month of outflows.
"As the March 2019 Brexit deadline looms, investors are seeking to diversify and manage their risk with global and mixed asset funds attracting strong inflows, as did Volatility Managed funds."
In terms of asset classes, multi-asset was the best-selling with £539m in net retail sales, while funds classified as Other, which includes the Targeted Absolute Return, Volatility Managed, Protected and Unclassified sectors, were the second best-selling asset class with net retail sales of £36m.
All other asset classes experienced outflows; Property experienced
a net retail outflow of £28m, Fixed Income saw £164m exit the asset class, Money Market funds saw outflows of £292m, and Equities suffered outflows of £308m.
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