The Liberal Democrat NI spokesman called for more solutions and less rhetoric as the Northern Ireland secretary Brandon Lewis headed to Stormont for crisis talks after Sinn Fein’s historic victory.
Speaking after a minister hinted the protocol could be scrapped, Mr Carmichael insisted minds should focus less on point scoring.
He said: "The Northern Ireland election results show that the momentum is with the Alliance Party, who want compromise for the sake of lives and livelihoods, not more scrapping and threats.
“In the middle of a cost-of-living crisis and a war in Europe, the last thing we need is to shatter European solidarity for the sake of Tory egos.
"Boris Johnson's threats and rhetoric fuel uncertainty for families and businesses in Northern Ireland – we all deserve a little more caution and care from the Prime Minister."
His comments came after universities minister Michelle Donelan said scrapping the Northern Ireland Protocol “is on the table as one of the options”.
She told Sky News: “Our priority, of course, is to deal with the problem head on. We have a duty towards the people of Northern Ireland who are a fundamental part of the UK.
“As you point out, the Northern Ireland protocol is not working and I believe the concerns about that were reflected in the recent result that we saw in the election.
“We’re working at pace to resolve this. Nothing’s off the table.
“We’re negotiating with the EU to find a solution. As we’ve said nothing is off the table here. If we need to, we will trigger Article 16, but we want to try and negotiate as our first priority.”
Monday also saw Alliance leader Naomi Long criticise suggestions the Northern Ireland Protocol is threatening the Good Friday Agreement and preventing formation of government at Stormont.
She said: “What is threatening the Good Friday Agreement is the British government not playing an open hand with the people of Northern Ireland, using and abusing the protocol as an issue to try to garner support for their own cause.
“I think it’s time for the UK Government to resume its role as an honest broker in this process, to be open and honest with the people of Northern Ireland, with the political parties about what is possible and what is not.
“Ultimately this is Boris Johnson’s baby. The protocol was birthed on his watch.
"There is no point in telling us now it’s a disaster. It’s up to him to provide solutions, and those solutions have to be agreed with the European Union because that is the only thing that will bring certainty and clarity that business needs."
Earlier Taoiseach Micheal Martin defended the approach taken by the EU towards the Protocol.
He said: “I don’t think the assessment that is coming from the British Government is a fair assessment of the EU’s position.
“I think the European Union has been flexible, has demonstrated flexibility, but every time up to now that the European Union has demonstrated flexibility, it hasn’t been reciprocated.
“And that has made the EU more cautious in terms of the discussions with the United Kingdom Government.”