UUP leader Doug Beattie has said "violence will not resolve political difficulties" after recent trouble in loyalist areas.
Mr Beattie was speaking after Justice Minister Naomi long said politicians must take responsibility for "hyping up the language and the tensions" around the Northern Ireland Protocol.
Her comments came after loyalists torched buses in two separate incidents a week apart.
On Sunday night masked men forced the driver and passengers off a bus before setting it on fire in Newtownabbey.
An attack at the Bowtown estate in Newtownards on Monday November 1 was later linked to the Protestant Action Force, a cover name previously used by the UVF.
There has been speculation it was timed to coincide with a deadline previously set by the DUP to resolve issues around the protocol and Irish Sea border.
In September, DUP leader Sir Jeffrey Donaldson threatened to collapse Stormont "within weeks" if demands over the protocol were not met.
In a wide-ranging interview with the Irish News yesterday Ms Long also said she was concerned about young people caught up in the recent round of violence.
"I don't want to see another generation of young people criminalised and in trouble because of careless and inflammatory language the politicians are using," she said.
Mr Beattie last night said "all governments, institutions and politicians must understand that their words have consequences".
“The Ulster Unionist Party has been absolutely clear," he said.
"Violence will not resolve political difficulties.
"We have been trying to calm tensions and offer leadership."
Mr Beattie added that the "Northern Ireland institutions exist to give people a voice and that voice cannot be stifled by ignoring concerns or collapsing the assembly.
"Politics is the way out of this mess and we must all, regardless of political party, be mindful and respectful of our differing points of view," he said.
“The Ulster Unionist Party will speak to everyone.
"We want more engagement, not less.
"We will do all that we can to keep the institutions on the road and use politics to deal with the serious issues facing Northern Ireland and its people.”
A spokesman for the TUV said: "Nobody wants to see that.
"Obviously we would discourage anyone from engaging in violence and we have been unambiguous about that but it is not appropriate to say that those are the results of people hyping up the rhetoric in relation to the protocol.
"If Naomi Long is concerned about rhetoric the people that are responsible for the worst of that are not unionist politicians, it's the EU who (on Monday) were telling us they were 'ready for peace but prepared for war'.
He added that Ms Long has been a "champion" of the EU and "has been behind them on every turn on this".
"Can you cite me a unionist politician who has used more inflammatory language than the EU used this week?" he said.
The DUP was contacted but did not comment.
