Barclays put a block on new stop loss orders this morning, just as the EU membership vote got underway.
The move could be the bank's way of shielding itself from any wild swings in exchange rates that could happen shortly after the results of the vote are announced.
City A.M. understands that the restriction on new stop loss orders applied from 7am today, while the bank has only been accepting orders via manual voice execution, as opposed to through the electronic system, since Monday. All other electronic orders are available to clients.
A note to clients explaining the restrictions has been shared with Reuters by one of Barclays' clients.
A Barclays' spokesperson said:
Our global sales, trading and research teams are helping clients navigate markets throughout the night and post the EU referendum decision by delivering a normal service for our clients at all times as far as market conditions allow.
Meanwhile, online money transfer startup Azimo revealed yesterday that it would be temporarily suspending money transfers from 6am this morning until "things have settled down on Friday and we can safely trade again".
Transferwise also announced earlier this week that it would not be taking incoming pound transfers from 7am this morning and outbound pound transfers from 6pm tonight.
Sterling has been less than steady in the run up to today's vote. This morning, it reached its highest rate against the dollar since last December, breaking through the $1.49 mark. The pound also rose 0.64 per cent against the euro to over €1.31.
Read more: Here's what Brexit might do to your tax bill
Meanwhile, analysts have predicted that the stock market will be particularly prone to movement tomorrow, regardless of which way the vote goes.
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