British Prime Minister Boris Johnson pushed Britain closer to a no-deal exit from the European Union on Monday, insisting he will not hold Brexit talks with EU leaders unless the bloc lifts its refusal to reopen the existing divorce deal - notably the Irish backstop.

Amid tough rhetoric from government ministers on Brexit, the pound sank to a two-year low against the euro as investors became nervous at the prospect of the UK leaving the EU at the end of October without an agreement on the terms of its departure.

Sterling fell by more than 1 percent to €1.10 and $1.22 – its lowest level against the dollar for 28 months.

On a visit to Scotland, Johnson repeated the message he has uttered many times since becoming prime minister last week. "The Withdrawal Agreement is dead, it's got to go," he said.

But once again he also sounded an optimistic note. "My assumption is that we can get a new deal, we are aiming for a new deal," he said during a visit to the Faslane naval base.

Johnson said the EU must drop a "backstop" intended to keep the Irish border open. The backstop would require the United Kingdom to remain aligned to EU customs rules if a future trading relationship falls short of ensuring an open border.

"What we want to do is to make it absolutely clear that the backstop is no good, it's dead, it's got to go. The withdrawal agreement is dead. It's got to go," Johnson continued.

Johnson is trying to pressure the EU to give ground by intensifying preparations for the UK to leave the bloc in three months without a deal.

"There must be some change from the EU and if the EU are not willing to move at all we must be ready to give the country some finality," Foreign Secretary Dominic Raab said on Monday, adding that London was "turbo-charging" no-deal preparations.

The 27 other EU members, though, say publicly and privately that the divorce settlement - including the backstop - is not up for barter.

Johnson became prime minister last week after winning a Conservative Party leadership contest by promising that the UK will leave the EU on the scheduled date of October 31 - with or without a deal.

Read more:

Boris Johnson hails ‘ties that bind UK’ as he heads to Scotland

No-deal Brexit: everything you need to know

Brexit Guide: where are we now?

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