Jeremy Corbyn’s suspension from the Parliamentary Labour Party (PLP) “went behind an agreement to reinstate” him to Labour “at all levels”, the High Court has heard.

The former leader of the opposition is considering legal action against Labour for “an injunction to restore the whip immediately”, his lawyers said at a remote hearing on Monday.

The Islington North MP was suspended from Labour in October for claiming that the scale of anti-Semitism in the party was “dramatically overstated for political reasons”.

He later attempted to clarify his comments in a statement, which he says was agreed with the party, saying concerns about anti-Semitism were “neither ‘exaggerated’ nor ‘overstated’”.

Mr Corbyn was reinstated as a party member by the National Executive Committee (NEC) following a meeting of a disciplinary panel three weeks after his suspension.

But his successor as party leader Sir Keir Starmer blocked him from sitting as a Labour MP, saying Mr Corbyn had “undermined” work to restore trust and confidence in the party’s ability to tackle anti-Semitism.

Mr Corbyn’s legal team is now applying for “pre-action disclosure” from the Labour Party ahead of an “anticipated claim” over his suspension.

On Monday, Mr Corbyn’s barrister Christopher Jacobs told Judge Lisa Sullivan: “We need to know the involvement of the Labour Party leader (Sir Keir) in accepting the NEC decision.

“We need to know the conduct of the Labour Party leader in accepting the agreement (that there would be) no requirement for further sanction and the matter would be closed.

“And we need to know the extent to which the decision to impose a second suspension … was influenced by third-party interventions.”

He said the decision to prevent his client returning to the PLP seemed to be the result of “political interference” and said Mr Corbyn’s treatment by Labour was “grossly unfair”.

Mr Jacobs argued that “the party and the party leadership in particular” went behind “the legitimate and final decision of the NEC” to reinstate Mr Corbyn, arguing that its “complete about-turn is perverse”.

I don't want to see the Labour Party tied up in court proceedings, I want to see the Labour Party out there campaigning

He also argued that the suspension of Mr Corbyn – who appeared to attend the remote hearing on Monday – from the PLP was “a fundamental breach of contract” in relation to his client’s membership of the party.

Mr Jacobs said Labour had breached a “settled agreement” to restore the party whip to Mr Corbyn.

He told the court that, at two separate meetings in late October and early November, “it was agreed that there would be no further sanction imposed in respect of my client”.

In written submissions, Mr Jacobs said Mr Corbyn was seeking minutes or notes of those two meetings, as well as documents related to chief whip Nick Brown’s “consultation” with Sir Keir about the decision to suspend Mr Corbyn.

Rachel Crasnow QC, for Labour, said the party had already provided “adequate disclosure”, adding: “There was no agreement in any event.”

She said Mr Corbyn’s proposed claim against Labour was “a straightforward contract claim based on two agreements: firstly, his membership of the party … and, secondly, upon a supposed agreement reached between his representatives and party representatives”.

Ms Crasnow argued in written submissions that Mr Corbyn’s “purpose of obtaining early disclosure from the party is to advance a political, rather than a legal, position”.

She added that disclosure was also unlikely to resolve the dispute without the need to bring legal proceedings because “this case has an important political significance to Mr Corbyn that will not be satiated by obtaining early disclosure”.

At the conclusion of the hearing, Judge Sullivan said she would give her ruling on Mr Corbyn’s application “as soon as I can”.

Before the hearing, Sir Keir told reporters: “I’m not going to comment on the particular case.

“I don’t want to see the Labour Party tied up in court proceedings, I want to see the Labour Party out there campaigning.

“My message across the Labour Party is: ‘Let’s all pull together’.

“We have got a pandemic to deal with, we have got a duty to deliver a better Britain at the end of this, let’s pull together and do that.”