The leader of the Democratic Unionist Party (DUP) has said he does not want to see Carla Lockhart leave the party.

Lockhart has called for the DUP to remove First Minister Michelle O’Neill from office by having Emma Little-Pengelly resign from her role as deputy first minister.

However on Thursday, the DUP confirmed that Little-Pengelly will not participate in joint engagements with O’Neill and permission will not be granted for the first minister to operate on a solo basis.

Gavin Robinson said he “hopes” that Lockhart will not leave the party and added: “We all share the same view that there needs to be political sanctions for the behaviour of Michelle O’Neill.”

It follows unionist anger over Sinn Féin’s involvement in protests which prevented a contentious Orange Order march in Portadown from passing along the mainly nationalist Garvaghy Road.

In a letter to party colleagues on Thursday, Lockhart said she will “take her own course” if O’Neill is not removed as first minister.

Other DUP representatives, including assembly member Diane Forsythe, have since backed Lockhart’s calls for O’Neill to be “removed from office”.

Maurice Bradley MLA also said removing O’Neill “would not, in itself, require the Assembly to collapse”.

A meeting of the party’s ruling officer committee was held earlier on Thursday.

Robinson said the decision among DUP MLAs to cease engagement with the first minister and deputy first minister was “unanimous”.

Lockhart is expected to resign from the party, the Belfast Telegraph, external are reporting.

Last week, the Upper Bann MP stepped down from the party’s officer board over Robinson not withdrawing Little-Pengelly to force O’Neill from their joint Stormont office.

On Thursday the DUP blocked O’Neill from attending the National Economic Council.

The meeting was due to be attended by the prime minister and all the devolved leaders.

“If anybody steps back and thinks about the pressures on our political institutions, the fragility of our political institutions and would they tolerate it in Scotland, Wales and England – I think the honest answer to that is, no they would not,” Robinson told BBC Radio Ulster’s Good Morning Ulster programme.

He said his party “will not take steps that will punish the people of Northern Ireland”.

“I’ve been very clear that there is a job of work to do that can only be achieved through the executive and my colleagues will be absolutely, fundamentally principled and absolutely, fundamentally robust in dealing with and for the people of Northern Ireland.”

He said the halting of engagement with O’Neill are “consequences” of the first minister “stepping outside her pledge of office”.

Other parties in the Northern Ireland Assembly have been critical of the DUP’s move.

O’Neill’s Sinn Féin colleague, Chris Hazard, told Good Morning Ulster there had been “no breach” by the first minister on the pledge of office.

“A stunt is exactly what it is, it’s pathetic, it’s petulant and it’s damaging, now it’s not damaging to Michelle O’Neill or Sinn Féin, it harms our local businesses, it harms our workers looking for better jobs and it frustrates families crying out for investments in public services.”

Hazard said Northern Ireland’s seat at the National Economic Council had been “sacrificed” as the prime minister and other devolved leaders are at the economic forum.

The Alliance Party MLA Kate Nicholl said Northern Ireland not being represented at Friday’s meeting of the National Economic Council was “so disappointing” and “completely baffling”.

The Traditional Unionist Voice (TUV) leader Jim Allister said “the DUP’s sham response today was beyond pathetic” adding “the DUP is interested only in clinging to office, not principle”.

The Ulster Unionist Party leader Jon Burrows told BBC’s Evening Extra programme the situation was a “political fudge” that was “all choreography and no consequences,” adding that the move would “probably galvanise Sinn Féin further at the ballot box.”

The Social Democratic and Labour Party’s (SDLP) Matthew O’Toole said “plunging this place into more political chaos is not a sensible strategic move for unionism”.