In this Oct 1, 2020 file photo, European Commission President Ursula von der Leyen takes off her protective mask prior to making a statement regarding the Withdrawal Agreement at EU headquarters in Brussels. (JOHANNA GERON / POOL PHOTO VIA AP)

Trade talks between the UK and European Union are “so tricky and so difficult” but there could be a positive outcome in the next few days, European Commission President Ursula von der Leyen said.

With face-to-face talks continuing in London, the German head of the bloc’s executive said on Tuesday there are still important questions to resolve around the so-called level playing field, a set of rules designed to ensure fair competition between businesses.

The negotiations, which have been going on since March, are now in their final days, with both sides’ parliaments needing time to ratify any agreement before the UK leaves the EU’s single market on Dec 31

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“At the moment being, we’re discussing how we replicate the control of the level playing field, be it state aid, be it norms -- environmental norms or labor norms, for example,” she told an online conference. “How we replicate that on both sides so that we can be clear there’s no regression from what we’ve achieved, and there is fairness over time.”

The negotiations, which have been going on since March, are now in their final days, with both sides’ parliaments needing time to ratify any agreement before the UK leaves the EU’s single market on Dec 31. An accord would establish tariff and quota-free trade in goods and cooperation in areas such as security and transport.

The UK, which doesn’t recognize the level playing field term, has rejected any idea that it signs up to EU standards without full control over how its own rules develop or change. The two sides are trying to find a solution that satisfies both.

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Prime Minister Boris Johnson’s spokesman, Jamie Davies, told reporters on Tuesday that the government is working hard to bridge the differences with the EU.

'We’ll see'

Negotiators are also wrangling over access to British fishing waters. The UK is holding out for a better deal on how it controls its fish stocks, something it sees as a matter of sovereignty. An agreement on the issue is a precondition for an overarching accord.

“We’ll see how the next days will go,” von der Leyen said. “I’m very clear again that we want an agreement, but not at any price, so we are well prepared for for both scenarios, and we will see in the next days how things turn out.”

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The sense of optimism has been shared by other figures in the past few days. Ireland’s prime minister, Micheal Martin, told the Irish Times that “there’s a landing zone for an agreement” and that he is hopeful of an agreement by the end of the week.

On Monday, French European Affairs Minister Clement Beaune said he hoped to see an agreement “in the next few days” while on Sunday, UK Foreign Secretary Dominic Raab said he believed there is “a deal to be done” in coming days.