Progressive Unionist Party (PUP) councillor Dr John Kyle said there was no equal treatment between the nationalist and unionist community in the Brexit process.
Dr Kyle said the aspirations and interests of the nationalist community was “carefully safeguarded” by the European Union.
The Belfast councillor, who appeared before the Northern Ireland Affairs Committee, said the implementation of the protocol has made it more difficult to trade between Northern Ireland and Great Britain.
“There are added costs, so the cost of purchasing or supplying goods from GB has gone up,” Dr Kyle said.
“I think there are the emotional elements to it, the inability to move your pet to England and then return without a pet passport.
“There are these practical and emotional implications of the regulatory border. There is an obstacle between Northern Ireland and the rest of United Kingdom which is more than just a body of water.”
A new raft of checks on goods at the ports of Belfast and Larne under the terms of the protocol have sparked anger among unionists and loyalists who feel Northern Ireland is being separated from the rest of the UK.
Talks are continuing between the EU and the UK Government to solve some of the issues linked to the protocol, but many unionists have called for the protocol to be scrapped.
Dr Kyle told the committee that there is a perception among the unionist community that their citizenship in the UK has been “altered”.
“I don’t think that there’s been just and equal treatment of both communities. I think that the ethos and aspirations and interests of the nationalist community were carefully safeguarded by the EU,” he added.
“The identity and ethos of the Unionist community, as equal citizens with everyone else in the United Kingdom, was sacrificed.
“They may be trade laws but they’re still laws.
“They may be regulations but they’re still enshrined in a legal framework and we are now subject to laws that are passed by 27 other (EU) states, but that do not apply within the rest of United Kingdom, and to most unionists that is a perception of an alteration in their citizenship in the United Kingdom.”
He added: “I think that there’s possibilities for economic benefits, but I would caveat that with saying that for many unionists, being British is more important than being prosperous.
“We’re not prepared to sort of go for an economic deal and sacrifice our British identity, that means much more to many unions.”
Peter Sheridan, CEO of cross-border peace-building organisation Co-operation Northern Ireland, said there are parts of the protocol that are having a material adverse impact across all parts of society.
He said leaders in the EU and Westminster assured that the implementation of the protocol would have as little as impact as possible on every day life in Northern Ireland.
“That is not what is happening,” Mr Sheridan said.
“From a nationalist perspective, they see it as a trade border, but they do express concerns about the UK extending the grace period unilaterally without the agreement of the EU and the damage that does to relationships.
“From unionism, they see it not just as a trade border, but as an identity and constitutional issue.
“It makes them feel less British than the UK and that increasingly Northern Ireland is becoming separate and distinct from the UK and that Northern Ireland’s relationship with the rest of the UK has been changed without their consent.”