European Commission President Jean-Claude Juncker attends a news conference after the extraordinary EU leaders summit to finalise and formalise the Brexit agreement in Brussels, Belgium November 25, 2018. REUTERS/Yves Herman

BRUSSELS (Reuters) - The head of the European Union’s executive, Jean-Claude Juncker, on Sunday urged the UK parliament to ratify the Brexit deal the bloc sealed with British Prime Minister Theresa May, saying it was the only one possible.

“This is the best deal possible. I’m inviting those who have to ratify this deal in the House of Commons to take this into consideration. This is the best deal for the UK, the best deal for Europe, this is the only deal possible,” Juncker said.

The chairman of EU leaders, Donald Tusk, stressed the EU would ratify the Brexit deal in time for the Brexit day on March 29, 2019 and was determined to build “as close as possible a partnership” with Britain in the future.

“We will remain friends until the end of days. And one day longer,” Tusk said.

At their joint presser concluding a quick Sunday summit of all EU leaders to approve the Brexit deal negotiated over 18 months, they refused to speculate on what would happen if British Prime Minister Theresa May loses the parliamentary vote.

“Those who think that, by rejecting the deal, they would get a better deal, will be disappointed,” Juncker said.