British Prime Minister Theresa May | Pool photo by Andy Rain/EPA Theresa May pushes to ease Brexit law through House of Commons Opposition accuses British PM of ‘power grab’ over proposed changes to key committees.

LONDON — Theresa May will attempt to change lawmaking rules to overcome her lost majority and ease new Brexit laws through the House of Commons.

MPs will vote Tuesday on a new motion that would automatically give the Conservatives a majority on key committees required to pass new laws, the Huffington Post and Independent both reported Thursday.

May lost her parliamentary majority in June after calling a snap election, but stayed in power because of a deal with the Democratic Unionist Party (DUP), who agreed to back her government on key votes.

The motion, which is due to be published Friday, would allow the prime minister to control the legislative agenda in the crucial committee stages of lawmaking without assistance from any other party.

The EU (Withdrawal) Bill, which started its passage through the House of Commons in earnest on Thursday and brings EU law onto the U.K. statute book, is already coming under fire from MPs who fear it hands executive powers to ministers during the Brexit process by giving them the authority to change legislation without consulting parliament.

A U.K. bill has three stages, called readings, and between second and third readings there is a committee stage where a bill is scrutinized clause by clause.

A public bill committee, which examines the details of a particular bill, normally consists of between 18 and 30 MPs, chosen by the committee of selection. By long-standing convention, the party balance on the committee matches the distribution of votes in the last general election.

The leaked motion states that House of Commons rules will be changed so that “where a committee has an odd number of members, the government shall have a majority.”

And “where a committee has an even number of members, the number of government and opposition members shall be equal, but this instruction shall not apply to the nomination of any public bill committee.”

In practise, this means should they win Tuesday's vote, the Tories will have a majority on every key committee, despite not having an overall majority in the Commons.

A government spokesperson said: "These proposals create the fairest balance between the opposition and government, and will ensure technical, procedural rules do not cause unwarranted delays to the business of parliament.

"The adjustments provide for maximum scrutiny with minimum disruption and delay, both to parliamentary proceedings and to the governance of the country," the spokesperson added.

Shadow Leader of the House Valerie Vaz told the Huffington Post: “This is an unprecedented power grab by a minority government that lost its moral authority as well as its majority at the general election.

“The British people will not understand how having voted to deny the Conservatives a majority, the Tories can alter the rules of parliament to ensure they have one."