The US is postponing a deal to remove tariffs on UK steel and aluminum because of London's threats to change trading rules in Northern Ireland.
The EU and the US have warned that changing the EU-UK accord could threaten peace on the island of Ireland.
A US commerce department official stated in a communication that talks with the UK on easing metals tariffs could not move forward.
The official cited US concerns at British threats to invoke the clause in the Northern Ireland protocol that would suspend checks on goods travelling to Northern Ireland from the rest of the UK.
The communication said that Washington informed the UK of the reason for the hold-up. Three people familiar with the matter said talks were stuck after Congress pressured the UK to not invoke the clause.
The government of Boris Johnson has said that it will invoke the power of the Articles 16 if a deal is not struck with the EU to ease restrictions on trade between Great Britain and Northern Ireland. The option remains on the table despite recent signs that the UK has softened its stance.
The EU and US agreed to suspend tariffs on steel and aluminum in October.
The deal provides relief from the Trump-era tariffs on steel and aluminum, but leaves UK steelmakers at a disadvantage because they still face steep duties on exports to the US. The UK has retaliated against US products with retaliatory duties.
The lack of movement on the Bourbon Alliance's negotiations was a concern for alliance members. The brokering of a deal between the US and EU would lead to some positive news for our UK-based members.
The single market for goods in Northern Ireland prevented a trade border with Ireland. Goods travelling from Great Britain into Northern Ireland must conform to EU rules, which means increased paperwork and delays in shipments.
The EU has suggested easing controls, but London says the proposals do not go far enough. The clause can be invoked by the UK or EU if they believe the arrangement has caused serious economic, societal or environmental difficulties.
The issue has attracted the attention of a substantial Irish diaspora in the US Congress, which has repeatedly called on the UK to honour the 1998 Good Friday Agreement that ended the region's three-decade long conflict. Senior Democratic legislators warned in November that the UK's threat to invoke Article 16 could cause a trade war and cause hard-earned peace.
The US president told Johnson not to allow the dispute with Europe to affect the peace on the island of Ireland.
The National Security Council at the White House said there was no link between the talks and the UK's position on the Northern Ireland protocol.
The commerce department wouldn't comment on the communication. The US and UK were consulting closely on bilateral and multilateral issues related to steel and aluminum.
The US trade representative's office said that they were talking to the UK.
The UK department of trade said there was no connection between the issue and the Northern Ireland protocol. Changes to the protocol are needed to protect the Good Friday agreement and Northern Ireland's place in the UK internal market.
The department had regular discussions with both the US trade representative and the commerce secretary on the issue and remained focused on agreeing a resolution that sees damaging tariffs removed.
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