LONDON, July 15 (Xinhua) -- An eighth member of British Prime Minister Theresa May's team resigned Sunday over her soft-Brexit proposals.

Robert Courts, who won the House of Commons seat left vacant when former Prime Minister David Cameron quit following the European Union referendum defeat, announced his decision on social media.

Courts resigned as a parliamentary private secretary saying he could not look himself in the mirror if he had been forced to defend the prime minister's soft Brexit plans.

Announcing his decision to his constituents in the Witney and West Oxfordshire constituency, Courts said he had taken the "very difficult decision to resign" so he can express discontent in votes in the House of Commons Monday with the Brexit blueprint agreed at May's Chequers meeting.

He added in his message: "I had to think who I wanted to see in the mirror for the rest of my life. I cannot tell the people of Witney and West Oxon that I support the proposals in their current form."

At the Chequers meeting May told members of her government team they were now expected to follow cabinet collective responsibility. That means members of her team who dissent either have to resign or be fired.

Brexit Secretary David Davis was the first to quit last Sunday, followed by Foreign Secretary Boris Johnson on Monday, with a number of ministers also resigning in the following days.

May faces a tough week in the House of Commons starting Monday as she starts the process to push through two parliamentary Brexit bills. Conservative party rebels have said they plan to submit amendments that could wreck the bills, causing a major Brexit headache for May.

The main opposition Labour party has indicated it will not support the amendments, according to media reports in London Sunday night. But Brexiteers on the Conservative benches say it will give them an opportunity to show their strength, and their opposition to May's soft-Brexit proposals.

Earlier May, in a national television interview, urged her MPs not to wreck her proposals by carrying out their threat to submit amendments, saying if they did so it would put at risk Britain's ability to make the necessary preparations for a no deal with the European Union.

"This is a time to be practical and pragmatic, backing our plan to get Britain out of the EU on March 29 next year and delivering for the British people," said May.