Parliament will on Tuesday try to shape the future of the country’s exit from the European Union by debating and voting on what changes they want May to seek to her Brexit deal.

With exactly two months until Britain is due to leave the EU on March 29, there is no agreement yet in London on how and even whether to leave the world’s biggest trading bloc after May’s plan was rejected by an overwhelming majority in parliament.

On Tuesday, MPs will debate and vote on May’s next steps, with some hoping to gauge the level of support for alternatives to her deal and others even seeking to wrestle control of the process from government.

It is not a rerun of the Jan. 15 vote on whether to approve May’s Brexit deal, but a chance to discover what sort of changes would be required to win the support of parliament, so the prime minister can try to renegotiate the agreement in Brussels.

At the centre of many pro-Brexit MPs’ concerns is the Irish “backstop”, an insurance policy aimed at preventing a hard border between the Republic of Ireland and the British province of Northern Ireland. It would require EU rules to apply in Northern Ireland if no other solutions can be agreed.

Senior Conservative lawmaker Graham Brady has put forward a proposal, known as an amendment, calling for the backstop to be removed and replaced with “alternative arrangements”.

That has won the backing of May and some Brexit campaigners, but a new compromise proposal, led by both Conservative pro-EU and pro-Brexit MPs, to return to Brussels with two options is also gaining support.

It calls for the backstop to be renegotiated or if that fails to leave on World Trade Organization rules at the end of 2021.

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