IMF chief Kristalina Georgieva welcomed news that Britain has reached a deal to leave the European Union but cautioned Thursday the details remain to be seen.

"This, of course, is welcome," she said of the Brexit deal announced earlier Thursday.

"We would like to see the agreement being reached," she told reporters at the start of the International Monetary Fund annual meeting.

"When there is a will, there is a deal... and my hope is that the will holds in all quarters. So let's see whether that happens."

Prime Minister Boris Johnson announced a Brexit withdrawal deal Thursday and it seemed one step closer to becoming reality after EU leaders endorsed the withdrawal agreement.

A summit of heads of state and government "endorsed this deal and it looks like we are very close to the final stretch," EU Council summit host Donald Tusk told reporters after the leaders met British Prime Minister Boris Johnson.

Britain's parliament is expected to vote on the deal on Saturday, ahead of the October 31 deadline for the divorce. But pro-EU MPS hope they can defeat it and Brexit can still be delayed to allow a general election or a new referendum on whether to leave the EU at all.

In Washington, Spain's Economy Minister Nadia Calvino said the Brexit drama has been a "Damocles sword" hanging over the world economy and creating uncertainty.

Georgieva said the possible Brexit breakthrough was 'welcome' news
Georgieva said the possible Brexit breakthrough was 'welcome' news AFP / Andrew CABALLERO-REYNOLDS

She said she hopes a deal -- once it is finalized -- will "unleash some dynamic positive forces" that will help boost growth.

"Now the ball is in the UK court," she said at a debate on the global economy on the sidelines of the IMF meeting.

The IMF estimates Brexit uncertainty will cut three to five percent off Britain's economy but also has slowed EU growth and contributed to a global weakening as well.

After posting GDP growth of 2.4 percent in 2017, the currency union slowed to 1.9 percent last year.

And the IMF's latest World Economic Outlook, released Tuesday, cut the estimates for 2019 to 1.2 percent and to 1.4 percent for 2020 -- with all the members of the currency union seeing slower growth.

World Bank President David Malpass agreed the Brexit saga has created uncertainty that has been weighing on the world economy.

"In particular, Europe's economy has slowed substantially," he said at a news briefing.

"So if there were more certainty in the trade relationships in Europe that would be very helpful.