By William James
LONDON (Reuters) - British Prime Minister Theresa May could clear the final hurdle standing between her and the start of Brexit negotiations on Monday when lawmakers will thrash out the final wording of a bill giving her the power to start the EU exit process.
In a debate due to begin later on Monday the government will call on lawmakers to throw out changes to the bill made by the upper house of parliament, arguing that May and her ministers need freedom to operate without restriction to get a good deal.
If successful, May could be ready to start a two-year negotiation period, as defined by Article 50 of the EU's Lisbon Treaty, as early as Tuesday.
"Please don't tie the prime minister's hands," Brexit minister David Davis said on Sunday, in a plea to lawmakers in May's Conservative Party who have threatened to rebel.
The task of keeping lawmakers happy and persuading the upper house of parliament that the government has listened to their concerns will fall to Davis, who is expected to speak in parliament around 1600 GMT.
The debate comes after the government lost two key votes in parliament's upper chamber in recent weeks, adding conditions into the bill saying May must guarantee the rights of EU nationals living in Britain and give lawmakers more powers to reject the final terms she reaches with the EU.
To overturn those changes Davis must ward off a potential rebellion in the lower house, where May only has a slim majority, from a handful of pro-EU Conservatives who say parliament should be able to prevent the government walking away from negotiations and leaving without a deal.
However, a source with knowledge of cross-party discussions on the legislation played down the likelihood of success for dissenters. "I just don't think the numbers are there ... the prospects of either amendment passing (in the lower chamber) are slim," the source said.
After a two hour debate and at least one vote, the bill is then sent immediately back to the upper house for debate and approval, currently expected to start from 2030 GMT.
May's spokesman echoed Davis's call for lawmakers to approve the bill on Monday. "We have been clear that we want the bill to be passed unamended," he told reporters.
"We've also been clear throughout that we are determined parliament will be engaged all the way through the process and afterwards ... What we can't do is have anything which would tie the prime minister's hands as she goes into these negotiations."
The unelected upper house, wary of being seen as trying to block the outcome of last June's Brexit vote, is not expected to fight for their changes a second time, providing Davis strikes a conciliatory tone and acknowledges their concerns.
If they approve the bill, it will then be sent to the Queen for symbolic approval which could be granted as early as Tuesday morning.
(Reporting by William James; Editing by Dominic Evans)