The pound brushed its lowest level since mid-February as the UK currency tracked a deepening sense among investors that Westminster’s cross-party talks seeking a consensus on a Brexit agreement were faltering.

At the same time, a move away from risk across global markets left sterling looking exposed, and sent it towards the lower end of its trading range.

Sterling on Wednesday fell 0.5 per cent to trade at $1.2838 in afternoon trading in London, close to its lowest level since February 15. February’s intraday low was $1.2770.

As talks between Theresa May and the opposition leader in London flag, the prime minister challenged Jeremy Corbyn to make up his mind on whether to back her Brexit compromise plan. She meanwhile prepared to put her job on the line in a House of Commons vote in the first week of June.

Mrs May told the Labour leader the government would bring forward legislation to ratify a revised Brexit deal on June 4 or 5. Defeat would probably mean the end of the road for the prime minister and her attempt to take Britain out of the EU.

In talks lasting about an hour on Tuesday night, Mrs May said the government would propose a close customs arrangement with the EU and uphold workers’ rights and environmental protections, meeting some of Labour’s demands.