Britain could begin the formal process of leaving the European Union as early as Tuesday if legislation approving the move passes its final hurdles on Monday.
Both houses of the UK parliament will vote on the EU Withdrawal Bill later. If it is passed, the bill would allow Prime Minister Theresa May to invoke Article 50 of the Lisbon Treaty, which governs the relationships between EU member states.
That would give the UK a two-year window in which to hammer out a divorce deal with the other 27 EU governments. The negotiations are expected to be tough, and there is no guarantee that a deal could be reached in the time available.
Government ministers have urged the House of Lords not to stand in the way of the bill if, as expected, MPs vote to remove amendments on Monday afternoon.
Any delay in the parliamentary process could mean the process would be pushed later in the month, as the UK government wants to avoid a clash with the Dutch elections, which are held on Wednesday.