Sterling jumped more than 0.5% against the U.S. dollar on Wednesday.
The pound was last up 0.4% at $1.2265, after spiking to as much as $1.2292. It was also up against the euro by 0.2% at 89.54 pence (EURGBP).
The British currency has been on the back foot in early London trading on media reports that British Prime Minister Boris Johnson faces rebellion in his cabinet if he leads the country to a no-deal Brexit.
Jane Foley, a senior foreign exchange strategist at Rabobank, said the market remains highly sensitive to Brexit news and so rhetoric from key players in the Brexit decision-making process could have an impact.
Prime Minister Boris Johnson has consistently said the United Kingdom will leave the EU on Oct. 31 with or without a deal.