Britain and the European Union (EU) have reached a deal on their post-Brexit trade relations, British media reported Thursday.

British Prime Minister Boris Johnson is expected to confirm it at a press conference in London on Thursday, the reports said.

Johnson is quoted by British media as saying that "the deal is "done."

"All of our key red lines about returning sovereignty have been achieved," the BBC quoted an important government source as saying.

Meanwhile, European Commission President Ursula von der Leyen told a press conference in Brussels that "We have finally found an agreement. It was a long and winding road, but we have got a good deal to show for it."

She adds that it is "fair" and "balanced", and it was "right and responsible" for the two sides to pursue it.

The deal came with only a week to go before the Brexit transition period ends on Dec. 31, 2020.

The historic deal will mean zero tariffs and zero quotas and would mean Britain has "taken back control of our money, borders, laws, trade and our fishing waters," the Evening Standard newspaper quoted a British government source as saying.

The British parliament would still need to ratify the deal by the end of the year before it can be implemented on Jan. 1, 2021. The EU is likely to impose "provisional application" of the agreement until MEPs vote on it in 2021.

Britain left the EU on Jan. 31, 2020. The two sides have been locked in talks since March to determine their future relations.