Welcome to Hard Talk on the BBC World Service with me, Stephen Sacker.

My guest today is a member of the EU Mandarin class steeped in the intricacies of Brussels procedure,

whose current post-EU ambassador in London is posing quite a challenge.

Portuguese bureaucrat, Zhao Vall de Almeida, is the first post-Brexit representative of the EU in the UK,

and he's already hit significant turbulence. Prime Minister Boris Johnson is backing out of one key

element of the treaty he signed to codify the UK's post-Brexit relationship with Brussels,

and at the heart of the issue is Northern Ireland,

where a deal was struck to avoid the return of a hard border

between the North and the Republic of Ireland to the south.

Northern Ireland remained inside the single market,

and the UK accepted that border checks and paperwork would be carried out

on goods flowing between the British mainland and Northern Ireland to ensure no violation

of EU standards on foodstuffs, medicines and other products likely to end up in Ireland.

It was an arrangement that infuriated the unionist community in Northern Ireland,

and now it's prompted a full-scale crisis. The Johnson government has declared it will no longer

implement the deal that it's signed. The EU says that is illegal and has threatened both court

action and the possibility of trade sanctions.

Brexit never looked like being completely harmonious, but why has it turned so toxic?

Well, Joao Valé de Almeida joins me now. Ambassador, welcome to hard talk.

Thank you for having me.

It's a pleasure to have you.

I want to start with some words of yours

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