LABOUR is to force a Commons vote on scrapping the one per public sector pay cap.

Jon Ashworth, the Shadow Health Secretary, called on Tory MPs to join his party in backing moves to end the "unfair" cap south of the border, with a motion to be debated on Wednesday.

However, any vote on Labour's motion would not be binding on Theresa May’s Government.

But the Opposition is seeking to capitalise on Conservative support for public sector workers to receive a pay increase and the Prime Minister’s lack of majority to pressure her to take action sooner than previously hinted.

Nicola Sturgeon, the First Minister, has already pledged to scrap the pay cap for public sector workers in Scotland.

Labour’s parliamentary bid follows a former top Treasury official labelling the cap unsustainable in the long-term.

Lord Macpherson of Earl's Court, who spent a decade as permanent secretary to the Treasury until 2016, said a failure to properly cost any lifting of the one per cent cap would leave the deficit unacceptably high.

He added Mrs May and Chancellor Philip Hammond would have to decide either to cut spending or hike taxes to pay for it.

Mr Ashworth told Sky News's Sunday with Niall Paterson: "What the Government needs to do is understand the concerns of the people who work in our National Health Service and wider public services and get rid of this pay cap.

"We keep getting briefings in newspapers and suggestions that the Government is sympathetic and wants to do something, and 'Oh, it's terrible and we accept that but let's see where we get to'.

"We're bringing a vote to the House of Commons on Wednesday and those Conservative Members of Parliament who have sincerely said they believe the pay cap should go, we're calling on them to vote with us and I'm calling on your viewers to lobby those Conservative Members of Parliament and let me know what they say.

"We can put an end to the pay cap on Wednesday for the NHS staff if they vote with us," said Mr Ashworth.

Asked if Labour would support a union-backed general strike, the Shadow Secretary of State replied: "People go on strike for industrial reasons, they don't go on strike for political reasons and...the Labour Party supports people who take industrial action.

"But we don't want it to get to that stage. We don't want to see a strike. We don't want to see nurses going on strike and wider public servants going on strike.

"The way to avoid that is for the Government to understand the concerns of public sector workers and get rid of this unfair pay cap," he added.

Last week, Sir Michael Fallon, the Defence Secretary, said the Government fully understood that public sector workers had taken their "share of the pain" of deficit reduction and signalled that the Chancellor was looking at the issue.

The respected think-tank, the Institute for Fiscal Studies, has said if public sector pay were to rise in line with inflation for the next three or four years it would cost the public purse £6 billion to £7bn more than continuing with the cap.

Commenting on the speculation, Lord Macpherson told BBC Radio 4's Westminster Hour: "Generally pay caps aren't sustainable in the long term. So, the Government does need to find a way of getting off this policy."

The Treasury is due to send out letters within weeks setting out the remit for public sector pay review bodies for next year's pay round and Mr Hammond is under pressure to allow them greater flexibility to recommend more generous rises.