Standard & Poor's (S&P) and Morningstar have put UBS's Property Securities Fund on hold after the departure of a key staff member.
The research houses took action after UBS replaced the New York-based chief investment officer of its global real estate securities (GRES) unit, Bruce Ebnother.
"This represents the most significant change to UBS's GRES team over the past 18 months," S&P fund analyst Kelly Napier said.
"We consider Mr Ebnother's departure a material loss given his leadership role, market experience, and involvement in building up the real estate securities capability over many years.
"Further, we recognised and valued his contribution and oversight to the UBS Property Securities Fund, which has a strategic 15 per cent global allocation."
Ebnother will hand over his responsibilities to the GRES division's new chief investment officer, Mark Thorpe-Apps.
Thorpe-Apps was previously with AIMS Financial Group in Sydney as executive director of funds management.
S&P had rated the UBS Property Securities Fund with three stars last month.
Morningstar's previous recommendation on the UBS Property Securities Fund was investment grade.
"It's not a surprise to see a change given the consistently poor performance of this strategy," Morningstar co-head of research Tim Murphy said.
Both research houses will reassess their opinion on the strategy later in the year.
