The British government struggled Thursday to overcome American opposition to its plans to breach the Brexit withdrawal agreement with the European Union, after Democratic presidential candidate Joe Biden became the latest U.S. politician to express alarm.
Prime Minister Boris Johnson's move to break parts of the EU divorce deal relating to Northern Ireland has triggered fears it could undermine the 1998 Good Friday peace accord that ended decades of violence between Irish nationalists and British unionists.
``We can't allow the Good Friday Agreement that brought peace to Northern Ireland to become a casualty of Brexit,'' Biden tweeted.
``Any trade deal between the U.S. and U.K. must be contingent upon respect for the Agreement and preventing the return of a hard border. Period,'' he wrote.
Britain and the EU jointly promised in the Brexit agreement to ensure there are no customs posts or other obstacles on the Northern Ireland-Ireland border. The open border is key to the stability that underpins the peace settlement.
British Foreign Secretary Dominic Raab is in Washington this week, and has been trying to assuage American concerns that a pending government bill would undermine Northern Ireland peace, if passed by lawmakers.
He is meeting U.S. politicians including House Speaker Nancy Pelosi, who has warned that Britain won't secure a much sought-after trade deal with the United States, if it undermines the peace accord.
Raab insisted the U.K. has an ``absolute'' commitment to the Good Friday Agreement. He described Britain's planned law as ``precautionary'' and ``proportionate.''
Johnson argues the law is intended to be an insurance policy against unreasonable behavior by the European Union that could threaten the unity of the U.K. by disrupting trade between Northern Ireland and the rest of the U.K.
The bloc has demanded the U.K. drop the plan by the end of September or face legal action.
The bill, which began its journey through Parliament this week, has also caused an uproar in Britain.
Five former British prime ministers have criticized Johnson's willingness to break international law, and the government's top legal civil servant and most senior law officer for Scotland have both resigned.
In an attempt to quiet unease among lawmakers from Johnson's Conservative Party, the government late Wednesday offered a compromise that would require Parliament to vote before the government took any actions that broke international law.
The U.K. withdrew from the EU's political institutions on Jan. 31 but remains in a tariff-free transition period until the end of the year while negotiators work out the terms of a future trade relationship.