The pro-remain Conservative MP Dominic Grieve was given a reprieve from deselection by his local party on Friday – but was warned against continuing to campaign against Brexit.

Grieve, who chairs parliament’s intelligence and security committee and served as attorney general in David Cameron’s government, lost a vote of confidence held by his local party association in late March. Members in his Beaconsfield constituency were angered by his opposition to Brexit, Jackson Ng – the association’s chair – told him in a letter on Friday.

But Ng stopped short of commencing proceedings to deselect Grieve, because he said such action “serves no constructive purpose”.

He wrote: “While we recognise that Brexit has imposed great strain on our party, you will know that your recent conduct and voting record has been a considerable disappointment to the majority of our members.

“Your recent comment that you have ‘never felt more ashamed to be a member of the Conservative party’ has been especially hurtful to our members.”

Grieve, who has campaigned against the hardest forms of Brexit and has worked to ensure that parliament has a significant influence over how the process is managed, was warned to display a greater willingness to see the UK leave the European Union.

“The overwhelming view of our membership is that the government must deliver Brexit and respect the views of the voters in the referendum,” Ng wrote. “The view of our association membership is that they profoundly wish for you to play a more positive role in the coming months on this matter. We feel it is crucial that you should do so.”

Ng did not respond when asked what practical action he would deem sufficient to stave off the threat of deselection.

Grieve has also argued for a second referendum, in opposition to most of his party. Nevertheless, the news that his local members had expressed no confidence in him as their MP in March led some prominent Tory figures to leap to his defence.

Among them was the leading Brexit campaigner and former foreign secretary, Boris Johnson, who said he was “sad” to hear the news. “We disagree about EU, but he is a good man and a true Conservative,” he said.

Grieve has not responded to a request for comment.