The new head of the European Commission has said there will not be enough time for the UK and European Union to reach a comprehensive trade agreement by the end of 2020, saying the two sides “must prioritise”.

However, in a broadly conciliatory speech at the London School of Economics this morning, she said the UK and EU’s post-Brexit partnership could be “unprecedented in scope”.

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Von der Leyen’s address to her old university came ahead of a key meeting with Prime Minister Boris Johnson in Downing Street later today in their first head-to-head since she took the reins from Jean-Claude Juncker.

The PM will argue against an extension to the negotiating period and insist that any deal must be wrapped up by the end of the year.

Yet von der Leyen said: “Without an extension of the transition period beyond 2020, you cannot expect to agree on every single aspect of our new partnership.”

She added: “It’s not an all or nothing thing, it’s a question of priorities.” Von der Leyen and Johnson’s respective positions leave open the possibility of a bare-bones trade deal being reached by the end of 2020, which could be added to later.

Tough negotiations

Addressing the negotiations, von der Leyen warned that the more the UK diverges from the EU’s standards, the less access it will get to “the world’s largest single market”.

She said she wants a trade deal that features “zero quotas, zero tariffs, and zero [product] dumping”, but said this means the UK would have to promise to stick to the current “level playing field” agreements.

Level playing field rules ensure the UK is aligned with the EU on things like labour and environmental standards. Many in the Conservative party argue that the UK should diverge from these rules, which they see as overly onerous.

Yet von der Leyen said: “Whatever diverges from level playing field decreases uncomplicated access to the single market.”

The European Commission president said that security is one area in which the EU and UK must stay closely aligned.

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“The threat of terrorism is real,” she said. “The nature of today’s threats means noone can deal with these challenges alone.”

The UK’s security and espionage apparatus is one of the most effective in the world, and the government will feel this is an issue it can use for leverage in the talks.

‘A new future’

Von der Leyen lamented the fact that the UK was leaving the European Union in her speech, saying that “the result of the referendum was a bitter pill to swallow”.

However, she said “the bonds between us will still be unbreakable, we will still contribute to each other’s societies”.

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“It is time for the best and oldest friends to build a new future together,” she said, “and as only true friends can I want to be very honest about what lies ahead”.

“Our partnership cannot and will not be the same as it was before… it cannot and will not be as close as it was before.”