The British government faces another nerve-rattling test this week as its flagship Brexit legislation is picked over once again by a restive parliament.
The upper House of Lords, which wants to keep Britain close to the European Union after the UK leaves in March, will rake over the EU (Withdrawal) Bill on Monday, before it returns to the lower House of Commons on Wednesday.
Last week, Prime Minister Theresa May narrowly survived votes in the Commons on changes suggested by the unelected Lords, overturning the upper house amendment seeking to keep Britain aligned to the EU’s customs union.
May also persuaded rebels in her governing centre-right Conservative Party to reject a Lords amendment that would have allowed parliament to stop the government from leaving the European Union with no deal on new trading arrangements.
But now May faces the prospect of having to go through the wringer all over again in a fresh bout of parliamentary ping-pong.
“We recognise the concerns people have about the role of parliament,” May told BBC television.
But she added: “Parliament cannot tie the hands of government in negotiations.”
A summit of European leaders on June 28 is fast approaching, and May does not want to go to Brussels on the back of a stinging defeat in her own parliament.
Wednesday’s Commons vote required last-minute concessions, and pro-EU Conservatives warned they could yet seek to defeat May if she backtracks on promises to give parliament a greater say on the final withdrawal deal.
The EU (Withdrawal) Bill would formally end Britain’s membership of the bloc and transfer more than 40 years of European law on to the British statute books.
May is on a tightrope as her Conservative minority government relies on the backing of 10 MPs from Northern Ireland’s Democratic Unionist Party for a slim majority in the 650-seat elected Commons chamber.
And pro-EU rebels on the Conservative backbenches are proving hard for May to satisfy.
Dominic Grieve, the former attorney general who heads up the faction, told BBC television that a future vote on a Brexit deal could see May tumble.