The UK’s Financial Conduct Authority (FCA) published a discussion paper on Wednesday that aims to examine the practice of retail investors gaining exposure to illiquid assets through open-ended funds, such as mutual funds.

The FCA acknowledges that investing in illiquid assets, such as real estate and infrastructure investments, provides investors with benefits such as diversification and the potential to earn strong long-term investment returns. Yet, at the same time, these holdings can pose problems if redemption demand spikes unexpectedly.

“Open-ended funds that invest in illiquid assets can encounter difficulties if investors expect to be able to withdraw their money at short notice,” the FCA’s paper says. “These difficulties can be exacerbated if an event in the market triggers an upsurge in redemption demand, or conditions change in the market for the underlying assets.”

The FCA paper follows from the surprise result of the U.K.’s Brexit referendum vote in June 2016, which led to some issues with funds devoted to illiquid assets. “Liquidity management issues arose in some U.K. open-ended property funds” after the Brexit vote, the FCA paper states.

As a result, the FCA’s paper has been published with the aim to “gather more evidence to decide whether changes to our regulatory approach are needed to enhance market stability and promote competition in the sector, while protecting consumers.”

The FCA paper sets out a variety of possible policy approaches, noting that one of the key issues in this area is balancing the interests of investors who want to withdraw their money and those who want to stay invested.

“This discussion paper is a great opportunity for all stakeholders to think carefully about the management of risk, particularly around redemptions, if investors are looking for a quick exit. We want to engage with fund managers and the investors whose money they manage to understand what problems they think exist,” says Megan Butler, executive director of supervision, investment, wholesale and specialist at the FCA, in a statement.

“Specifically, in the context of open-ended funds, we want people to consider how well the current rules address those problems, and what further regulatory intervention might be needed,” she adds.

The deadline for feedback on the paper is May 8. The FCA says it plans to publish a response later in 2017 after considering the results of the consultation.