LABOUR’S army of registered supporters should be excluded from taking part in future leadership elections, Tom Watson, the party’s deputy leader, has suggested as the power struggle moves to the ruling National Executive Committee today.

Jeremy Corbyn, the odds-on favourite to be re-elected as Labour leader when the result is announced on Saturday, would put the party on a general election footing if he does regain its crown.

But Owen Smith, his challenger, has warned that if there were an early election Labour could be “decimated”.

As NEC members meet this afternoon for what could be a very long meeting stretching into the evening, Mr Watson will press for excluding those who pay a fee as registered supporters from voting in future leadership contests.

It is thought as many as 130,000 registered supporters are eligible to take part in the current one; last year, Mr Corbyn won 84 per cent of this section, which then totalled 106,000.

Critics have claimed their inclusion has allowed the leadership election to be hijacked by far Left groups with their own agenda.

Mr Watson argued that their inclusion – introduced by former Labour leader Ed Miliband to broaden the franchise – had been “very rushed” and “unpopular”.

He has suggested abandoning the one person one vote model and returning to an electoral college, which was split between parliamentarians, ordinary members and trade unionists. But this would be seen as an attempt to block a left-winger like Mr Corbyn from becoming leader in future.

The other key issue will be a return to electing members of the shadow cabinet, abandoned by Mr Miliband in 2011.

Mr Watson and many of his parliamentary colleagues want the MPs alone to decide who sits alongside the leader on the Commons front bench but Mr Corbyn wants the membership to be involved, saying there is a “thirst for democracy” within the party. One suggestion is that a third of shadow cabinet ministers could be chosen by the leader, a third by MPs and a third by members.

Mr Corbyn also wants the membership to have a greater involvement in the NEC but it is thought he will not present specific proposals at today’s meeting, suggesting the NEC should reconvene after next week’s annual conference to consider its approach in detail and then conduct a consultation before determining its position on the way forward.

But any delay until after conference would mean that Mr Corbyn’s proposals would be decided by a potentially new-look NEC, whose membership will have a greater representation of the grassroots, which is likely to be more supportive of the leader’s plans.

Any decisions taken today by the NEC will have to go to conference, which begins in Liverpool on Sunday, for approval.

Mr Watson told BBC Radio 4's Today programme: "We've had a very bruising summer, we are going to get a new leader elected on Saturday, we all think there is the likelihood of a very early general election and so we have got to put the band back together.

"For me, the heart of our party is the parliamentary party...and we have got to bring people back in. To have an elected shadow cabinet, not an appointed shadow cabinet, is one way we do that," he explained.

Mr Watson confirmed the NEC would discuss the MP-only plans and the proposal to select the shadow cabinet by a mix of members, the leader and MPs.

He insisted he was "open-minded" on the options but pointed out that a members' vote would impose a financial burden of as much as £300,000 on the party because of administration costs.

Asked if he would urge Labour MPs who have been critical of Mr Corbyn to serve in the shadow cabinet if the incumbent retains power on Saturday, Mr Watson said: "Yes, all members should consider how they can best serve their party - that's why they become MPs."

When asked directly if he believed Mr Corbyn could be elected prime minister, the Midlands MP replied: "Jeremy could easily be a Labour prime minister. We have got to change what we do, how we campaign, we have got to change how we do our policies and make sure that we prioritise other policy areas that we have not been focusing on this summer.”

He added: "But whoever wins that leadership, we have got to swing in around that leader and make sure that they are the most electable leader we have."

Sources close to Mr Corbyn confirmed he would, if re-elected, put the party on an election footing for a possible poll as early as the spring.

The move was being seen as a bid to instil discipline among restive MPs, who are now mulling over how to respond if, as widely expected, he holds on to his position as leader.

It is believed the Islington MP is minded to instruct his MPs to vote to for any early election called by Prime Minister Theresa May: under the Fixed Term Parliaments Act it has to be supported by at least two-thirds of the Commons.

But Mr Smith warned it would be difficult to unite the party under Mr Corbyn's leadership, telling BBC One's Breakfast programme: "I've been warning for months now that there was a danger that we could be going into an election sooner rather than later.

"If we had an election right now, the polls are telling us that we would be decimated in that election, so the risks are enormous and the need therefore to unite the party is very great but it will be very difficult."