PM Mariano Rajoy dissolved the region's parliament on Friday
The Department of Foreign Affairs says Ireland does not recognise Catalonia's declaration of independence.
In a statement, the Department of Foreign Affairs says: "We are all concerned about the crisis in Catalonia.
"Ireland respects the constitutional and territorial integrity of Spain and we do not accept or recognise the Catalan unilateral declaration of independence.
"The resolution of the current crisis needs to be within Spain's constitutional framework and through Spain's democratic institutions.
"Ireland supports efforts to resolve this crisis through lawful and peaceful means."
Speaking earlier this month, Taoiseach Leo Varadkar also said Ireland would not recognise an independent Catalonia.
The UK, Germany and France are among others to throw their weight behind Spain's prime minister.
While the President of the European Parliament says "no one in Europe will recognise the independence of Catalonia".
Antonio Tajani says the rule of law should be restored in the Spanish region.
In a statement, he says: "The declaration of independence voted on today in the Catalan Parliament is a breach of the rule of law, the Spanish constitution and the Statute of Autonomy of Catalonia, which are part of the EU's legal framework.
"No one in the European Union will recognise this declaration.
"More than ever, it is necessary to re-establish legality as a basis for dialogue and to guarantee the freedoms and rights of all Catalan citizens."
The Spanish Prime Minister Mariano Rajoy dissolved Cataluña's parliament on Friday and called an election after the region finally declared independence.
Mr Rajoy invoked the emergency measures contained in article 155 of the country's constitution in response to Catalan MPs voting to break away from the Spanish state.
He said he would seek to declare the vote illegal.
Mr Rajoy said Cataluña's police chief would be sacked and central government departments would take over functions from the regional parliament.
The Spanish government is shutting down Cataluña's foreign affairs department and dismissing its delegates in Brussels and Madrid.
Regional elections will be held on December 21st.
Mr Rajoy said it was important to call fresh elections to ensure "nobody can act outside the law", but added "we never wanted to come to this point".
He said the aim was to return Cataluña to "normality and legality" as soon as possible.
The Government has updated travel advice for Irish citizens in Spain, as the crisis in Cataluña deepens.
The Department of Foreign Affairs says people should be prepared to adjust their travel plans "at short notice if necessary".
Spain arrived at the constitutional crisis after officials in the northeastern region held an illegal independence referendum on October 1st.
The vote was marred by violence as national police intervened, but Catalan leaders said more than two million people turned out and that 92% wanted to break from Spain.
After independence was declared on Friday, thousands turned out to celebrate outside the Catalan government palace.
They watched events inside from two giant screens as they clapped and shouted "independence" in Catalan.
The motion, which was boycotted by opposition parties, said Catalonia was an independent, sovereign and social democratic state, and called on other countries and institutions to recognise it.
However, after the announcement from the Catalan parliament, Mr Rajoy hinted that their celebrations would be short-lived by saying they had done "something that is not possible - declare independence".
The supporters who had gathered in Sant Jaume Square in Barcelona to hear the Catalan declaration were told of Mr Rajoy's decision to sack the region's parliament.
A band took to the stage and the crowd defiantly began singing and dancing to music, shouting: "We are not moving."
Meanwhile, hundreds of anti-separatist protesters took to the streets waving Spanish flags to demonstrate against the independence declaration.
Miquel Iceta, the leader of Catalonia's Socialists, welcomed Mr Rajoy's announcement of a new election.
In a tweet, he said: "In the most sad day due to a wrong and irresponsible decision by the separatists, we see a ray of light."
Additional reporting: Jack Quann