It's nearly two years since the UK left the EU but the stand-off over how Brexit affects Northern Ireland continues.
A fifth round of talks in Brussels today between Lord Frost and the EU's Maros Sefcovic failed to lead to a breakthrough.
Even though Brussels has offered to lift 80% of checks on goods, Lord Frost said in a statement that 'significant gaps remain across most issues'.
He says the UK essentially wants no checks on goods that are destined only for the market in Northern Ireland.
The checks arise because under Boris Johnson's 2019 Brexit deal, Northern Ireland remains in the EU's single market and the customs union.
Today, Maros Sefcovic acknowledged the Northern Ireland Protocol had led to "unintended consequences".
He also warned that the post-Brexit trade deal and sorting out the Protocol were "intrinsically linked". That suggests if Britain acts to trigger Article 16, effectively tearing up the Protocol, a trade war might ensue.
Earlier, Louise Haigh, the Shadow Northern Ireland Secretary, urged the Government to reach a deal on the Protocol soon.
"Boris Johnson and Lord Frost signed up to every single word of it and at the time heralded it as an ingenious solution that would help protect the Good Friday Agreement," she said.
"I would just urge them to compromise and show more humility."