Emily Thornberry has confirmed Labour will not vote next week for Boris Johnson’s snap general election because the prime minister is a “manifest liar”.

Johnson will try for a second time to force an early election on October 15 after MPs rejected his first bid.

But opposition parties are worried Johnson could move the date of the poll until after the UK has left the EU without a deal once parliament has agreed to it.

Thornberry told BBC Radio 4’s Today programme: “If we vote to have a general election then, no matter what it is that Boris Johnson promises, it is up to him to advise the Queen when the general election should be.” 

SEE ALSO: Why Doesn’t Labour Want A General Election?

Asked if Labour would vote against the government motion on Monday, the shadow foreign secretary said: “Yes.”

If Johnson tries to call an election using the Fixed Term Parliaments Act, he has to win the support of two-thirds of MPs.

Jeremy Corbyn will hold a conference call with other opposition leaders on Friday morning to discuss tactics.

One Labour source told HuffPost UK it would best for the party to let Johnson “stew in his own juices” and delay an election until after parliament orders him to extend Article 50.

SNP Westminster leader Ian Blackford has also suggested he would not support moves for a snap general election until after the prorogation of parliament next week.

“We have to be careful that we don’t walk into a trap. I want the removal of Boris Johnson. I want an election. But we’ll do it in a way that there are not unintended consequences,” he told Sky News.

The European Union (Withdrawal) (No 6) Bill went through the Commons on Wednesday but also needs to pass the House of Lords on Friday before Parliament is prorogued next week.

If the Bill passes in the Lords, a no-deal Brexit will be prevented, but there is much horse-trading to be done before that.

Johnson last night said he would “die in a ditch” rather than request the EU for an extension to Article 50.