The leader of Catalonia, Carles Puigdemont, is due to address the regional parliament on October 10 amid concerns in Madrid that parliament may vote for a unilateral declaration of independence.
Security is tight ahead of the plenary session scheduled for 6 p.m. (same as Prague time), with police guarding public buildings and closing off a park surrounding the regional Catalan parliament in Barcelona.
Separatist politicians have said they expect a declaration based on the October 1 referendum, in which Catalan officials say people voted overwhelmingly for secession from Spain.
But hundreds of thousands of people demonstrated against breaking away in Barcelona over the weekend.
They say the referendum did not show the true will of the region because many of those who want to stay in Spain did not vote.
Ahead of Puigdemont’s speech, the Spanish government called on Catalonia's leader “not to pursue a path of no return and not to make any unilateral independence declaration."
EU President Donald Tusk called on Puigdemont to respect “the constitutional order and not to announce a decision that would make … dialogue impossible."
Under Catalonia's referendum law -- deemed unconstitutional by Madrid -- a vote for independence in the assembly on October 10 would start a six-month process envisaging divorce talks with Spain before regional elections and a final act of separation.