Sterling edged down today as the European Union failed to set a date for Britain's departure from the bloc while the UK parliament squabbled over Prime Minister Boris Johnson's call for an election to break the deadlock.

EU ambassadors agreed in principle to a delay beyond the October 31 deadline, but will not decide the length of the extension until Monday or Tuesday, an official said. 

The pound fell slightly on the news and was down 0.22% against the dollar at $1.2821 by 5.15pm, though it held above the one-week low of $1.2790 hit on Thursday after Johnson called for an election. 

By the same time the euro was level on the day against sterling at £0.8639. 

Sterling is down 1.3% so far this week, ceding half the gains made last week when it rallied the most in two years. It is still up 5% to the dollar this month as risks of a no-deal Brexit have tumbled. 

Boris Johnson's spokesman said the government would push ahead with Brexit if lawmakers did not agree to an election.

Labour leader Jeremy Corbyn says he will only support an election if a no-deal Brexit is taken off the table.