European Commission President Ursula von der Leyen outlined her vision for post-Brexit relations between the EU and UK in Strasbourg on Tuesday, as European legislators debated the body's mandate for upcoming negotiations with London. 

During her parliamentary address, Von der Leyen stated the EU was willing to accept Britain leaving the bloc on World Trade Organization (WTO) rules, but stressed that a free-trade deal would be preferable.

"The UK can decide to settle for less. But I personally believe that we should be way more ambitious," she said. 

She commended British Prime Minister Boris Johnson's intentions on shared social protection and climate action, saying this could be the basis of level-playing-field obligations between Britain and the EU.

"I've heard ambition in Boris Johnson's speech, ambition on minimum wage, ambition on parental payments... I have heard ambition on cutting carbon emissions, ambition on guaranteeing that our firms are competing in full fairness," Von der Leyen said.

"This is what we also want. Let us formally agree on these objectives. We can formally trigger an upward dynamic competition that would benefit both the United Kingdom and the European Union," she continued.

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Post-Brexit trade talks: EU sets out terms of its 'exceptional offer'

Red lines

The EU commissioner added that the body was prepared to offer Britain unrivaled access to its single market in a free-trade deal, "something we have never ever before offered to anybody else," describing Johnson's desire for the UK to be "a global champion of free trade" as "music to our ears."

"Of course, this would require corresponding guarantees on fair competition and the protection of social, environmental and consumer standards. In short: This is plain and simply the level playing field." 

While details are yet to be agreed, London says it will be leaving the EU's single market and customs union after the end of the transition period on 31 December 2020. 

The European Parliament, which will need to approve any final deal, is due to vote on Wednesday on a resolution backing the Commission's negotiating mandate for Brexit negotiations next month. 

The two sides are expected to be at loggerheads over state aid legislation, banking, competition policy, labor law, criminal justice, Gibraltar, the European Court of Justice and data protection among many other issues. 

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Brexit: What changes and what stays the same?

Finance 

During the plenary session, the EU's chief negotiator, Michel Barnier, homed in on London's commitments on banking – stressing that Britain should not be under any illusion that market access for financial services would be given on a permanent basis. 

UK financial services companies are set to lose unfettered access to Europe, and vice versa, after the transition period, with the EU hoping to keep its right to so-called "equivalence rulings" – being able to choose which UK firms are able to trade within the bloc and in what manner.

Barnier stressed that such rulings would remain under tight EU control, with no special treatment for Britain, despite London pushing for a mechanism that would allow some kind of joint control on equivalences.

"There will be no general, global, permanent equivalence," with the UK, said Barnier. Adding: "There will be no common management."

Fisheries and overseas territories 

The single market status of the British overseas colony of Gibraltar on Spain's south coast was also raised by several legislators, with socialist MEP Iratxe Garcia Perez stating: "We will demand that Spain has the final say in discussions between the European Union and the United Kingdom concerning Gibraltar, as has been ratified in the Commission's guidelines."

Her conservative colleague Esteban Gonzalez Pons added: "Let us defend the decolonization of Gibraltar; let it not become a tax haven, let it not remain a tax haven." 

The MEP from Spain's right-wing Popular Party (PP) also alluded to disputes over fishing territory with the UK, as the EU hopes to bring the issue of fisheries to a close by taking the UK out of the EU's Common Fisheries Policy, giving it the right to set its own fishing quotas and stop foreign vessels accessing its waters. 

However, the bloc is calling for "existing reciprocal access to fishing waters and resources" as part of a trade deal.

"Let us defend our fishermen, who have to risk their lives every day in order to earn their living," Gonzalez Pons told MEPs. 

Freedom of movement

Croatian minister Nikolina Brnjac, who was representing the European Council, focused on London's intention to discontinue free movement as one of the key factors in determining the UK's access to the single market and trade with the EU.

"What we should focus on is the Union's interest in achieving an outcome that is fair and equitable for all member states and their citizens," the MEP said.

"It should be clear, however, that this cannot amount to giving the UK the same benefit as a member state, especially in the light of its red lines."

Dutch liberal lawmaker Sophie in 't Veld condensed the EU's overriding message: "Boris Johnson cannot have his cake and eat it."