Prime Minister Theresa May intends to trigger Britain’s withdrawal from the European Union as close as possible to the EU summit taking place on March 9 and March 10, according to two government officials involved in Brexit planning.

The latest on the timing suggests May is keen to initiate the formal process of leaving the bloc well in advance of a self-imposed March 31 deadline. She cannot act before Parliament passes a bill giving her permission to do so, and that will happen very close to the summit.

The upper house is due to debate the draft law next week and may amend it, which could cause some delay. The timetable is for a final vote in the House of Lords on March 7 and the U.K. budget comes out March 8, making that an unlikely day for May to pull the trigger.

The fact that the government is planning to give the EU formal notice in early March helps damp speculation a move later in the month was more likely after Brexit Secretary David Davis said “9th, 10th is not a date I recognize in terms of our timetable.”

One of the government officials added that early March would also be an act of sensitive diplomacy given the celebrations planned for March 25 to mark the 60th anniversary of the Treaty of Rome, which set the foundations for the union.

Any amendments to the wording of the bill made by the Lords would mean the draft law going back to the lower House of Commons, which would have to accept or reject the changes. That could see the legislation passing back and forth in a process known as “ping pong” to agree a mutually acceptable version. Even so, the leader of the opposition Labour Party in the Lords said this week the process shouldn’t lead to any “extended” delay.