BOOM: UK set to formally trigger Brexit process.
Giving official notice under Article 50 of the Lisbon Treaty, it will be delivered to European Council president Donald Tusk later.
In a statement in the Commons, the prime minister will then tell MPs this marks “the moment for the country to come together”.
It follows June’s referendum which resulted in a vote to leave the EU.
Mrs May’s letter will be delivered at 12:20 BST on Wednesday by the British ambassador to the EU, Sir Tim Barrow.
If Rex Tillerson’s State Department would get busy on a bilateral free trade deal with the UK, that would give them a better negotiating position with the eurocrats in Brussels.