Britain’s Parliament voted Saturday to delay Boris Johnson’s Brexit deal, handing the prime minister a humiliating defeat.

The 322-306 vote forced Johnson to seek another delay, but the defiant prime minister said he will push ahead for the United Kingdom to leave the European Union as planned.

Parliament passed a law last month which forces the prime minister to send the EU a letter seeking a three-month postponement of the Oct. 31 Brexit deadline — something Johnson has said he didn’t want to do.

Despite his reluctance, Johnson sent the letter, refusing to sign it.

European Council President Donald Tusk tweeted he’d received the letter and will “start consulting EU leaders on how to react.”

Even though he asked for the delay as required, Johnson was unyielding.

“I will not negotiate a delay with the EU and neither does the law compel me to do so,” he said. “I will tell our friends and colleagues in the EU exactly what I’ve told everyone in the last 88 days that I’ve served as prime minister: that further delay would be bad for this country, bad for the European Union and bad for democracy.”

Saturday’s vote mandated all of the legislation needed to implement Brexit be passed before a vote is held on Johnson’s plan.

If the UK exits the European Union without an agreed upon plan for the governmental divorce, such a “no-deal” Brexit could ravage the British economy, experts have said.

Parliament’s Saturday vote was intended to prevent a “no-deal” Brexit, which Johnson threatened would happen if his plan wasn’t okayed.

Johnson said he will introduce the legislation to push through his deal in the coming days. He still believes he can command “overwhelming” support.

Hundreds of thousands of anti-Brexit protesters marched through London to Parliament Square Saturday, demanding a new referendum on leaving the EU.