JOHN McDonnell has failed to back Richard Leonard over the latter’s pledge a UK Labour government would rule out a second independence referendum.

The shadow chancellor was asked in a television interview yesterday whether if in power his party would refuse to allow a second vote on the issue.

He said: “We’ll consider whatever proposals come from Scotland, of course. These are devolved issues that need to be discussed overall.”

Leonard promised earlier this year UK Labour would make a commitment to block a second vote in its next General Election manifesto.

In the same week, Labour leader Jeremy Corbyn said he would not rule allowing a new vote if he became prime minister.

McDonnell was pressed on Leonard’s claim and refused to give a guarantee such a commitment would be made in the UK party’s manifesto.

He told the BBC’s Sunday Politics Scotland: “We think [a referendum] is a complete distraction and we maintain our opposition. Of course the manifesto will be determined in the normal democratic process.”

Leonard promised in September that UK Labour’s next General Election manifesto would commit the party to oppose a second independence referendum.

“We want to be absolutely clear to the people of Scotland that there is no case for a second independence referendum. We just had a referendum in 2014,” he said.

“We think that settled the will of the people of Scotland, and I don’t think there is any support for a second independence referendum, which is why we are going to categorically, in our manifesto in the lead up to the General Election, which may come as soon as later this year, state our opposition to the holding of a second independence referendum.”

Last night an SNP spokesman said that Leonard again found himself “ignored by his bosses in Westminster”.

He added: “The reality is that it would be utterly undemocratic for any Westminster government to deny the Scottish Government its clear mandate, and to deny the Scottish Parliament from exercising its right.

“Richard Leonard’s streak of ineffectualness continues and John McDonnell was right to reject the indefensible position to deny the people of Scotland a choice on their constitutional future.”

McDonnell’s indication that a Labour government would consider Scottish proposals for a new vote on independence was seized on by the Tories.

Scottish Conservative constitution spokesman Adam Tomkins said: “This is further evidence that Labour are comically weak when it comes to standing up to the SNP’s independence demands.

“It’s no wonder the party is tanking north of the Border when its two most important figures couldn’t care less about Scotland. It’s clear a Labour government would lie down and allow Scotland to be ripped out of Britain. That’s a shameful failing on Labour’s part, and one which completely betrays the majority of voters in Scotland.

“This all goes to show, once again, that only the Scottish Conservatives can stand up to Nicola Sturgeon and the SNP.”

It is the second major policy difference to emerge between UK Labour and Scottish Labour in the last week. McDonnell backed Philip Hammond’s Budget plans to raise the 40p higher income threshold to £50,000, saying it puts money in pockets. But Leonard publicly distanced himself from his party south of the Border for the first time saying raising the higher rate threshold “should not be a priority for the Scottish Government” and called for the richest to pay their fair share.

People in Scotland are taxed at 41% on earnings above £43,430 and Leonard has said his party would not support raising that level. McDonnell said the Scottish Labour leader had “quite rightfully” put forward proposals refusing to raise the higher tax band in line with Westminster.

He said: “Richard Leonard, quite rightfully because taxation is devolved, put forward the Scottish Labour Party proposals. The intellectual basis is this – we all agree on the common principles of a fair taxation system. That has to reflect the demographic that we represent and also it has to reflect the devolved nature of our decision making in our country at the moment. Richard Leonard, quite rightfully, and the Scottish Labour Party have actually come forward with their tax proposals which are based upon fairness, based upon raising additional monies that will be put into public services. That’s exactly the tax proposals and principles that we’re putting forward here.”