Labour Leader Jeremy Corbyn is facing a revolt by a quarter of his MPs on the vote to trigger Article 50 and begin the Brexit process.

Leading figures including former leadership contender Owen Smith are among those who have already indicated they will vote against the measure.

The government is expected to bring a Bill to the Commons within days to formalise the decision to trigger Article 50, following a ruling by the Supreme Court on Tuesday which decreed that MPs must be consulted.

But as many as 60 Labour MPs have indicated that they will defy the will of the British people and oppose the measure.

Leading the rebellion is Owen Smith, who has vowed to vote against the measure despite the people of his Pontypridd constituency backing Brexit during the referendum in June.

Writing for the Guardian, Smith said: “I cannot, in all conscience, stand by and wave through a course of action that I believe will make our people poorer and our politics meaner.

He added: “No doubt taking that stand will make me an enemy of the people.

“But I was elected to parliament to exercise my judgment on behalf of the people I represent, and I can be ejected from parliament by those same people at the next election if they choose.”

Smith holds a majority of 8,985; his constituency has been represented by a Labour member for the last 95 years.

Meanwhile, shadow ministers Tulip Siddiq and Catherine West have indicated that they would be prepared to quit the Labour front bench to vote against Article 50.

However they may be spared, as, speaking to the BBC on Tuesday, Shadow Brexit Secretary Kier Starmer hinted that the Labour rebels may not face sanctions over the matter.

“This is a difficult set of decisions for many colleagues who feel very strongly about these issues,” he said. “We are handling it collegiately, talking to people and discussing it in the Labour party in the way you would expect.”

The rebellion is unlikely to derail the triggering of Article 50 as Conservative members, on the whole, are not expected to vote against the measure. But Labour’s relaxed attitude toward its rebels, coupled with Corbyn’s confirmation on Tuesday that Labour “will seek to amend the Article 50 Bill” has led to concerns that the process will be severely hampered.

Those fears were not allayed by Labour’s Emily Thornberry, who has threatened “hand to hand combat” over the matter.

“Article 50, if it is going to be triggered, we will not get in the way of it, but we will try and amend the legislation in order to ensure that they keep coming back, that we keep an eye on them,” she told BBC’s Newsnight.

“And, if necessary, there will be hand-to-hand combat on this,”

Demanding a white paper, Thornberry said that the Prime Minister, Theresa May “can’t say that she acts on behalf of the whole country without actually negotiating with Parliament, without listening to Parliament.”

Addressing the Commons at the start of Prime Minister’s Questions on Wednesday, May confirmed that a white paper will be forthcoming.