Private bankers at Credit Suisse have reportedly told ultra wealthy clients to accelerate moving assets out of the UK by January.

A lack of clarity around Brexit could cause "turmoil" ahead of a rescheduled parliamentary vote on the Brexit deal on January 14.

The move comes at a time when the super rich are already leaving UK assets and diversifying their portfolios.

Credit Suisse is sounding the alarm on Brexit uncertainty after advising some of its wealthiest clients to consider accelerating plans to move assets outside the UK ahead of a rescheduled vote on Prime Minister Theresa May's deal in January.

Private bankers at the Swiss lender reportedly contacted key clients to suggest that many customers had already opted to move assets outside of the UK, and that they should consider doing the same.

Credit Suisse made the suggestion in the aftermath of Prime Minister May's decision to postpone a vote on Brexit until the new year, which the bank said prolonged a period of "turmoil", according to the Financial Times. Meanwhile, UK businesses will be told to prepare for a no-deal Brexit immediately, The Sun reported on Tuesday.

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The bank pushed back against the FT story, with a Credit Suisse spokesman saying that this advice is not the bank's official line: “Credit Suisse does not currently hold a house view that clients should move assets out of the UK due to Brexit or other political developments in the UK,” the spokesman said.

Still, it's another sign that market uncertainty over the UK's decision to leave the EU elevated with investors wary of a potential no-deal or a left wing government led by Jeremy Corbyn in the event of a general election. It follows a trend of banks and asset managers moving funds and businesses out of the UK since the Brexit vote ahead of the official leaving date of March 29 2019.

The pound has been down for much of 2018, as has the UK housing market and the benchmark FTSE 100 share index. The FTSE is trading down 0.7% as of 9.05 a.m in London (4.05 a.m EST).