LONDON, Dec. 6 (Xinhua) -- Negotiators from Britain and the European Union (EU) resumed their talks in Brussels on Sunday in a "final throw of the dice" as they try to secure a post-Brexit trade deal before the Brexit transition period expires at the end of this month.

British chief negotiator David Frost and his EU counterpart Michel Barnier met in a last-ditch effort to resolve the remaining issues in the trade talks as the time is running out.

Ahead of the meeting on Sunday, however, British sources warned there was no guarantee they would succeed, the London-based Evening Standard newspaper reported.

"We will be working very hard to try to get a deal," Frost told reporters at the Brussels train station as he arrived from London by Eurostar train. "We will be looking forward to meeting our European colleagues later on this afternoon."

The return to the negotiating table followed an hour-long call on Saturday between British Prime Minister Boris Johnson and European Commission President Ursula von der Leyen, in which they agreed on a final push to get an agreement.

The two leaders had phone conversations several times instead of face-to-face discussions due to the COVID-19 pandemic.

To bring life back to normal, countries including Germany, China, Russia, and the United States are racing against time to find a vaccine.

Frost and Barnier wrote on twitter on Friday that "the conditions for an agreement are not met, due to significant divergences on level playing field, governance and fisheries."

They agreed to "pause the talks in order to brief their Principals on the state of play of the negotiations."

Failure to reach a free trade agreement with the EU means bilateral trade will fall back on World Trade Organization (WTO) rules in 2021. Enditem