The prospect of a trade war between the EU and the UK seemed to move closer this week as the two sides failed to come to an agreement on trade with Northern Ireland.
Under a provision of the Brexit deal, known as the Northern Ireland protocol, the UK is required to implement regulatory checks on goods entering the country from the rest of the UK.
This is because Northern Ireland remains part of the EU single market, with no hard border with the Republic of Ireland, in order to safeguard the peace process in the territory.
A grace period delaying these checks is set to expire at the end of June. However, the UK government has indicated it could unilaterally extend this in order to prevent further disruption to trade across the Irish Sea.
In turn, this may lead to retaliatory action from the EU, possibly including legal action or the introduction of new tariffs and quotas on UK imports.
The row has been dubbed the 'sausage war' by some commentators, as one of the biggest points of contention is shipments of chilled meat products. The EU does not allow the import of these goods from non-member states such as the UK, which would mean products such as sausages are banned from being shipped within the UK from Great Britain to Northern Ireland.
While talks to resolve the issue took place this week between UK Brexit minister Lord Frost and his EU counterpart Maros Sefcovic, they broke up without agreement.
In a news conference, Mr Sefcovic refused to rule out measures such as tariffs and said the EU's patience is "wearing very, very thin".
"If the UK were to take further unilateral action in the coming weeks the EU will not be shy in acting swiftly, firmly and resolutely to ensure the UK abides by its international obligations," he stated.
Mr Sefcovis also said the EU had offered a temporary solution to the chilled meats issue while a more comprehensive trade deal is worked out, but Westminster has deemed this unacceptable as it would involve signing up to EU food standards.
Lord Frost, meanwhile, criticized the EU for operating the Northern Ireland protocol in an "extremely purist way", adding: "We don't see what risk is caused to Northern Ireland if chilled meats are imported there from GB."