Spain's Constitutional Court has suspended a session of the Catalan parliament scheduled for Monday in which local leaders were expected to declare Catalonia's unilateral independence from Spain.
Judges "ordered the suspension of the plenary that has been called for Monday in the (Catalan) parliament" while it hears an appeal lodged against it, a spokeswoman said, as the court confirmed the ruling in a written statement.
Catalan lawmakers had summoned regional president Carles Puigdemont to address the parliament about last Sunday's contested independence referendum in Catalonia.
The court warned that any session carried out in defiance of its ban would be "null."
It said the parliament's leaders could face criminal action if they ignore the court order.
Mr Puigdemont and other Catalan leaders have said they are not afraid of going to jail if Spanish authorities arrest them over their independence bid and they have defied the court's rulings in the past.
Mr Puigdemont carried out the referendum in defiance of a ban by the Spanish court and stern warnings from the national government in Madrid.
The speaker of the region's parliament said that the suspension of the planned session damages freedom of expression. Carme Forcadell said that parliament had taken no decision yet on whether Monday's session would go ahead.
She told reporters that the court's decision "harms freedom of expression and the right of initiative of members of this parliament and shows once more how the courts are being used to solve political problems."
The order from the Constitutional Court comes after Spain's government defiantly rejected calls for mediation over Catalonia's push for independence, which the country's king warned was endangering national stability.
As the European Union urged dialogue to ease the standoff between separatists in the northeastern region and Madrid, Catalan leaders had said they could unilaterally declare independence as early as Monday.
The tone of the crisis sharpened with Catalonia's president denouncing the king's intervention and Spain's government rejecting any possible talks.
"The government will not negotiate over anything illegal and will not accept blackmail," said a statement from Spanish Prime Minister Mariano Rajoy's office.
The dispute is Spain's worst political crisis in decades and images of police beating unarmed Catalans taking part in Sunday's banned independence vote sparked global concern.
Catalonia's president Carles Puigdemont called the central government's policies "disastrous" as the region's leaders pushed on with its bid to break away from Spain, angering Madrid and raising the risk of further unrest.
Pro-independence politicians did call for a full regional government session next Monday to debate the final results of the vote.
Spain's key IBEX 35 stock index plunged by more than 3% in the ongoing turbulence, with some big Catalan banks down more than 5%.
Scores were injured on Sunday as police moved in en masse, beating voters and protesters as they lay on the ground and dragging some by the hair.
European Commission Vice President Frans Timmermans has said it was "time to talk, finding a way out of the impasse, working within the constitutional order of Spain".
Speaking in an emergency debate in the European Parliament, he defended Madrid's right to "the proportionate use of force" to keep the peace.
A rich industrial region of 7.5 million people with their own language and cultural traditions, Catalonia accounts for a fifth of Spain's economy.
Catalan claims for independence date back centuries but have surged during recent years of economic crisis.
The regional government said 42% of the electorate voted on Sunday, with 90% of those backing independence. But polls indicate Catalans are split.
