Boris Johnson is coming under growing pressure from Conservative MPs and leading politicians in Northern Ireland to overhaul the region’s post-Brexit trade arrangements.

Eurosceptic Tory MPs and the pro-UK Democratic Unionist party seized on the European Commission’s move on Friday to override the Brexit treaty’s provisions on Northern Ireland to demand that the prime minister secure changes to the trade regime.

Business leaders have expressed concern the Northern Ireland protocol in the Brexit treaty, which is intended to prevent a hard border in the island of Ireland, is impeding the movement of goods from Great Britain to the region and have called for the UK and EU to jointly address the issue.

The European Commission on Friday sought to override the protocol, and potentially reintroduce border checks between the Irish Republic and Northern Ireland, because it wanted to stop coronavirus vaccines made in the EU from reaching the UK.

Brussels abandoned its move to invoke article 16 of the protocol, allowing the EU to act unilaterally, after objections from London, Belfast and Dublin.

Some of Northern Ireland’s politicians and business leaders are concerned at how the protocol, by requiring checks on goods moving from Great Britain to the region, is disrupting trade and increasing costs.

The checks arise because Northern Ireland, unlike Great Britain, is covered by EU customs rules and effectively stays in the bloc’s single market for goods after Brexit.

Arlene Foster, Northern Ireland’s first minister and leader of the Democratic Unionist party, said on Saturday that Mr Johnson should use article 16 of the protocol to take action to improve trade flow between Great Britain and the region.

She told the BBC: “The protocol is unworkable . . . we need to see it replaced because otherwise there is going to be real difficulties here in Northern Ireland.”

Mark Francois, chair of the European Research Group of pro-Brexit Tory MPs, said in an article for the Sunday Telegraph that the government should conduct a “complete review” of the protocol so as to “iron out” operational issues, and if necessary “consider replacing it entirely”.

Theresa Villiers, former Northern Ireland secretary, said the protocol must be “workable” and that required “some pragmatism” from the EU.

“It is in all of our interests to make the protocol work, but if there is ever an opportunity to push for a bit more common sense on the protocol, absolutely now is the time” she added.

Downing Street declined to comment, but Whitehall insiders said the government was committed to the protocol and stressed the UK was keen to engage in constructive discussions with the EU about its implementation. The European Commission did not immediately respond to a request for comment.

Micheál Martin, Ireland’s taoiseach, defended the protocol, saying it had only been in place for four weeks and as a result there were “bound to be teething problems”.

The EU is sticking to its plan to impose controls on coronavirus vaccines made in the bloc, although the European Commission has abandoned its move to invoke article 16 of the protocol.

Liz Truss, international trade secretary, said on Sunday Mr Johnson had been assured by European Commission president Ursula von der Leyen that there would be no disruption to the UK’s contract with BioNTech/Pfizer for its Covid-19 vaccine, which is being made in Belgium.