A British Union flag, also known as a Union Jack, flies beside European Union (EU) flags as pedestrians walk outside the Houses of Parliament in London, UK, on March 27, 2019. (CHRIS RATCLIFFE/BLOOMBERG)

LONDON - The latest trade talks between Britain and the European Union have been extended into the middle of this week, Downing Street said Sunday, as the UK government indicated optimism about signing a deal.

The negotiations, which restarted Thursday in London after they stalled last week, were originally expected to wrap up on Sunday.

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More talks are also planned in Brussels from next Thursday, the BBC quoted EU sources as saying

EU chief negotiator Michel Barnier had been due to leave the British capital on Sunday before continuing in Brussels on Monday but will stay on for discussions through Oct 28, according to a UK government official, who asked not to be identified.

The negotiations will then move to Brussels from Thursday, according to people familiar with the matter. The logistical developments do not reflect the state of progress in the talks, the people said.

Upon his arrival in London on Thursday, Barnier said "every day counts" and both sides shared a "huge common responsibility" in the negotiations.

Britain and the EU started their lengthy and bumpy post-Brexit talks in March after Britain ended its EU membership on Jan 31, trying to secure a future trade deal before the Brexit transition period expires at the end of this year.

The post-Brexit trade talks stalled last week, with Downing Street insisting there was no point in resuming discussions unless there was a change in stance from the regional bloc.

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There are big gaps between the two sides on such fields as the fisheries and state aid.

British Prime Minister Boris Johnson has said as the recent EU Summit in Brussels refused to offer London a Canada-style deal, Britain will prepare to embrace the Australia-style arrangement.

The Australia-style arrangement is considered a euphemism for failure to reach a free trade agreement, which means the Britain-EU trade will fall back on World Trade Organization (WTO) rules in 2021, local media said.