Pension funds, central banks and sovereign wealth funds made fewer new investments in the UK last year than in any other region relative to their existing portfolios.
That is according to a survey of 97 different investors with total assets of $12.08trn (£9.35trn), which now rate the UK's attractiveness at 5.5 out of ten, compared with 7.5 in 2016.
The research, carried out by Invesco, reveals that Brexit is seen as a significant negative, however, 54% of respondents don't intend to make changes to their allocation weightings until the long-term impact of leaving the EU is known.
"Many sovereigns confirmed their long-term commitment to existing UK investments, especially real estate and several high-profile UK infrastructure investments," Invesco head of EMEA sovereigns, Alex Millar, said.
"Despite the apparent negative sentiment around the UK, these are unlikely to move until the outlook for the UK as a preferred investment destination becomes clearer."
Sovereign investors ranked the US as the number one market in terms of attractiveness, scoring it eight out of ten, largely driven by interest rate rises and confidence of a 'pro-business' corporate tax regime since Trump was elected.
Germany's investment attractiveness increased from 7 in 2016 to 7.8 this year, making it the most popular market in Europe, with the country's perceived 'safe haven' status based on its economic strength cited as the main reason for this.
However, the research found that sovereign investors underperformed their target returns by an average of 2% last year, with governments reducing funding and canceling investments as a result.
"2016 was a challenging year for sovereign investors with concerns surrounding funding levels and return expectations remaining front of mind amid added macro-economic and political uncertainty," Millar continued.
"Demand for alternatives like infrastructure has been a consistent theme in past years, but this year the challenge of increasingly scarce supply is compounded.
"While investors have fewer asset allocation levers with which to respond, they are delving deeper into more supply-rich real estate markets, and looking to the US and Germany for opportunity and economic strength."