LONDON (Reuters) - Several of the contenders to replace Prime Minister Theresa May have said Britain should leave the European Union on Oct. 31, even if that means a no-deal Brexit.

FILE PHOTO: A pro-Brexit protester stands behind an EU flag ahead of the forthcoming EU elections, outside of the Houses of Parliament in London, Britain, May 22, 2019. REUTERS/Toby Melville

So can British lawmakers do anything to stop the country leaving the bloc without a deal?

May has announced she will resign next month and let someone else work out the way forward on Brexit, but her successor will be bound by most of the same constraints that saw her fail three time to get parliamentary backing for a deal.

Votes so far this year show there is no single plan that commands a majority in parliament, which is still arguing over when, how, and even whether, Britain should follow through on the public’s decision in a 2016 referendum to leave the EU.

However, there has been majority agreement in parliament against leaving the bloc without an exit agreement defining interim arrangements on issues like customs and citizens’ rights.

So, if the next prime minister is unable to break the deadlock in parliament or decides to actively target a no-deal exit, what could lawmakers do to prevent a no-deal departure?

POLITICAL PRESSURE

Elected members of the 650-seat parliament have a number of ways of expressing their opinion, but few of those have the power to force the government to change course.

Those opposed to a no-deal exit could seek an emergency debate, or use debating time allocated to opposition parties to vote on a motion expressing their view.

If supported by a majority this would create political pressure for a government rethink, but would not bind the prime minister to change policy.

LEGISLATIVE LEVERS

If a majority in parliament want to stop a no-deal exit without the government’s support, they will need to change the law to somehow prevent it - by demanding that the prime minister either delay the exit or cancels Brexit altogether.

Earlier this year lawmakers found a way to seize control of the parliamentary agenda and passed a law, despite government opposition, that mandated May to seek more time from the EU.

This alone would not have prevented a no deal, as the EU has to agree to any extension. Only legislating to revoke the Article 50 exit notification would stop Brexit happening.

Ultimately, May decided she would seek an extension anyway, which resulted in the new departure date of Oct. 31, but it showed lawmakers can find ways to impose their will if they have a majority.

However, that mechanism relied on the government seeking parliamentary approval for an exit deal. If the government was actively pursuing a no-deal strategy, lawmakers would not be able to hijack the legislative process to pass their own law and would need to come up with an alternative way to stop it.

While there is little precedent for this, parliamentary rules have proven flexible in recent months and speaker John Bercow, who wields considerable influence over procedural matters, has been supportive of attempts to block no deal.

END GAME

Parliament has the power to collapse the government through a vote of no confidence. This would require some Conservatives, or the allied Democratic Unionist Party, to rebel.

While this would halt policymaking and almost certainly force a change in leadership, it would not automatically change the legal fact that Britain will cease to be an EU member on Oct. 31.

Preventing a no deal would still require action by a successor government, appointed either after a general election or by the formation of a new governing coalition in parliament.