MADRID — Catalonia’s parliament will vote next week on whether to elect a jailed separatist leader as the region’s new president, as part of an ongoing effort to gain independence from Spain.

Parliamentary speaker Roger Torrent on Tuesday convened the plenary session in Barcelona for March 12, when Catalan lawmakers will vote on whether to make Jordi Sanchez their regional government’s leader.

Carles Puigdemont, Catalonia’s ex-leader who fled to Brussels to escape arrest, announced last week that he was temporarily withdrawing his bid to get his old job back and proposed Sanchez — his No. 2 in the Together for Catalonia party — in his place.

The vote is the latest push by Catalan separatists to advance their attempt break away from Spain — an effort the central government in Madrid has thwarted in the courts. The Spanish Constitution says Spain is “indivisible,” but the standoff has brought the country’s worst political crisis in decades and it shows no signs of ending.

Sanchez, a former president of a prominent secessionist civic group called Catalan National Assembly who was elected to parliament last December, has been held in a prison near Madrid since October.

He is detained while a judge investigates whether he orchestrated protests that hindered authorities’ attempt to halt preparations for a banned Catalan independence referendum on Oct. 1.

Sanchez has asked a judge to let him attend the plenary session. A letter from his lawyers to the Supreme Court, published Tuesday, argues that denying him permission to travel would be denying his personal rights and those of people who voted in December.

Next Monday, Sanchez would require a majority of parliamentary votes — 68 lawmakers — to be elected in a first round of voting. If he falls short of that number, in a vote 48 hours later he would require more votes for him than against him to be elected.

It wasn’t immediately clear whether Sanchez would have enough support to take office.