Johnson said he will press on "undaunted" with Brexit on Oct 31.

The PM must now ask the EU for an extension to that deadline after MPs backed an amendment aimed at ruling out a no-deal Brexit, by 322 votes to 306, reported BBC.

During the tough Parliament session, he told MPs as quoted as saying by BBC: "I will not negotiate a delay with the EU and neither does the law compel me to do so."

According to news agency Sputnik, Boris Johnson on Saturday told the UK parliament that the European Union is reluctant to delay Brexit any longer.

"I must tell the House in all candour that there is very little appetite among our friends in the EU for this business to be protracted by one extra day," Johnson said during the parliament sitting on Saturday morning ahead of the vote on his Brexit deal.

According to a CNN report, though the government's intention was to hold a straightforward vote on Johnson's deal, signed in Brussels on Thursday, its plans were scuppered when lawmakers passed an amendment crafted by former Conservative government minister Oliver Letwin, who has worked to prevent the UK from crashing out of the EU without a deal.

The PM vowed to bring the legislation on Oct 21 (Monday).

MPs could also be given another vote on the deal on Monday, if Commons Speaker John Bercow allows it, reported BBC.

Johnson had earlier repeatedly insisted that the UK will need to leave by the end of the month.

Under the terms of the so-called Benn Act, passed last month by MPs determined to prevent a no-deal Brexit, he has until 11pm to send a letter to the EU requesting an extension, reported BBC.

Meanwhile, Labour leader Jeremy Corbyn tweeted: "Boris Johnson's deal has been defeated. He must now obey the law - there cannot be a No Deal crash out from the European Union."

Irish Prime Minister Leo Varadkar reacted to the development and said: "The EU & UK agreed a Withdrawal Agreement on Thursday that defends Ireland’s interests. The Commons voted today to defer a decision on whether or not to ratify that agreement. To date, no request for an extension has been made by the UK Government."