European leaders side with Spain amid brewing tensions over Catalonia

German government spokesperson Stephen Seibert tweeted that "the sovereignty and territorial integrity of Spain are inviolable." He said that Catalonia's unilateral declaration of independence violates these protected principles.

Seibert said Germany supports "the clear attitude of the Spanish Prime Minister to ensure and restore the constitutional order." However, he also expressed the hope that "the parties will use all existing opportunities for dialogue and de-escalation."

Meanwhile, German Foreign Minister Sigmar Gabriel said Friday that only talks based on the rule of law and within the framework of the Spanish constitution can lead to a solution.

Bulgaria's Ministry of Foreign Affairs said in a statement that the country supports the territorial integrity of Spain.

"We call on all authorities in the country to engage in constructive dialogue, responsibility and respect for the rule of law -- to protect the stability, unity and security of citizens," the statement said.

Spanish Prime Minister Mariano Rajoy on Friday announced the immediate sacking of Catalan leader Carles Puigdemont and his government and called new elections in the region on Dec 21.

Moreover, Rajoy also sacked the chief of Catalan police, as well as closed the delegations of the Catalan government in Madrid and abroad.

The move followed the decision taken by the Catalan parliament earlier in the day to unilaterally declare independence of the region in the northeast of Spain.