MADRID (Reuters) - A judge will give his ruling on Monday on whether eight pro-independence Catalan politicians charged with sedition should be released from custody so they can contest a regional election set for Dec. 21, judicial sources said on Friday.

The eight, former members of Catalonia’s dismissed regional government, appeared before the Supreme Court on Friday to request their release while they await trial in the wake of a disputed independence referendum.

Catalan leaders, who previously held a slim parliamentary majority, made a unilateral declaration of independence in defiance of Spanish law on Oct. 27, leading to their arrest and forcing Madrid to take direct control of the region and call the election.

The face-off between Barcelona and Madrid has tipped Spain into its worst political crisis in four decades, prompted more than 2,800 companies to move their legal headquarters out of the region, and forced the government to cut growth forecasts.

It has also deeply divided people in the wealthy northeastern region and caused resentment in the rest of Spain.

Sacked regional vice-president Oriol Junqueras, one of his ERC party’s main candidates for the election, has asked to leave jail in order to campaign in the December vote, which pro-independence parties see as a de facto vote on secession.

The presiding judge will make his decision on the cabinet members’ custody public on Monday, judicial sources said. Any release would likely to be on bail and under strict conditions as the defendants await trial.

Junqueras and seven other former cabinet members were jailed on Nov. 2 pending trial on charges of sedition, rebellion and misappropriation of funds after organizing the illegal secession vote and declaring independence from Spain.

Earlier in November, the Supreme Court released Catalan parliament speaker Carme Forcadell on bail of 150,000 euros ($178,410) after she agreed to renounce any political activity that went against the Spanish constitution.

All eight former cabinet members have said they would abide by a ruling giving Madrid control over the region, according to their lawyers, although some of them said they did not agree with this unprecedented move stripping power from the rebel administration.

Campaigning for the Dec. 21 election officially starts on Tuesday.

The former president of Catalonia, Carles Puigdemont, in self-imposed exile in Belgium and subject to an arrest warrant from Spain for rebellion and misuse of public funds, has called the elections the most important in the region’s history.

Barely a quarter of Catalans want to continue with the project of creating an independent state, a survey by pollsters Metroscopia showed.

However, the same poll of 1,800 Catalans taken between Nov. 20 and Nov. 22, showed that separatist parties are forecast to win 46 percent of the vote, down slightly from 47.7 percent in a previous election in 2015.

Unionist parties combined would account for another 46 percent of votes, up from less than 40 percent last time.

The leaders of Catalan civic groups Asamblea Nacional Catalana (ANC) and Omnium Cultural, Jordi Sanchez and Jordi Cuixart -- who were imprisoned last month, also testified before the Supreme Court over their role in the independence drive.

($1 = 0.8408 euros)