Business groups have welcomed Parliament voting to seek a delay to Brexit.
But the CBI said that without a “radically new approach” to Brexit, a delay was only “a stay of execution”.
The British Chambers of Commerce added that it “leaves firms with no real clarity on the future.”
The pound fell a third of a cent against the dollar immediately following the vote.
The fall follows a climb to nine-month highs against the US dollar and a nearly two-year high against the euro after a vote on Wednesday.
Currency: Pound vs dollar
The latest vote came after MPs rejected Theresa May’s withdrawal agreement for the second time and then ruled out a no-deal Brexit.
However, business groups remained sceptical about the Brexit process.
Josh Hardie, CBI deputy