Catalonia will push forward with a planned November vote on independence, leader Artur Mas said on Tuesday, but in a modified way in an attempt to skirt restrictions imposed by the Spanish courts.

The poll will be open to Catalans aged 16 and over and organised by volunteers, without any formal electoral roll. Mas touted it as an alternative means for Catalans to express their opinion after Spain’s constitutional court suspended all campaigning and preparations for a planned referendum.

“On November 9 there will be a consultation, there will be ballots and ballot boxes,” said Mas. Unlike the planned referendum, which was originally made possible by a decree passed in the Catalan parliament, the poll would be held under “pre-existing frameworks” that allowed for citizen participation, he said.

The referendum was suspended after the court decided unanimously to hear a challenge by the central government. Caught between defying the court’s order and pro-independence parties pushing for the vote to go ahead regardless of its legality, Mas initially vowed to push forward.

On Tuesday he said the vote would have to be done “in a different form from what we had planned”, but insisted that it was not a step backwards. “Just the opposite. This government is committed to celebrating the referendum on November 9,” he said.

A poll this month showed that 23% of Catalans supported the idea of pressing ahead with an illegal referendum. The poll, done for Metroscopia and published in El País, found that 45% wanted the regional government to comply with the constitutional court’s orders.

Mas acknowledged that the non-binding vote would not be able to offer a definitive answer as to whether Catalans wanted independence from Spain, and he hinted that early elections could follow later. “November 9 is a lead-up to the definitive answer,” he said. “It’s clear that the most logical, final response is elections. That is what they fear in Madrid.”

In a nod to the grassroots movement that has driven the push for independence in the wealthy north-eastern region, Mas suggested that worries about international legitimacy could be dispelled by high levels of voter participation. “People must understand that a high turnout on November 9 would be a giant step towards a definitive referendum, which in this case would be elections.”

Spain’s prime minister, Mariano Rajoy, has repeatedly insisted that any referendum on independence would be illegal, as the country’s 1978 constitution prevents any region from unilaterally making decisions that affect all Spaniards.

On Tuesday, responding to initial media reports that Catalonia had abandoned its plans to hold a referendum, Rajoy called it “excellent news”.

Hours later, Mas took a swipe at Rajoy’s reaction, saying: “Sometimes excellent news only lasts a few hours.” Despite international interest in the Catalan secessionist drive and the escalating tension between Barcelona and Madrid in recent months, Rajoy and Mas have not spoken since July.

Alicia Sánchez-Camacho, the People’s party leader in Catalonia, called Mas’s alternative vote a farce. “This process has come to an end,” she said.

The deputy prime minister, Soraya Sáenz de Santamaría, said the central government was in the process of studying how it could challenge Mas’s latest proposal.

Tuesday’s announcement – seen as backtracking by many independence-minded politicians in the region – leaves Mas at odds with his political allies, including the pro-independence Catalan Republican Left (ERC), which props up Mas’s minority government. “We continue to move forward, but at the moment we are not as united as we were 10 days ago,” Mas said.

Mas urged his political allies to stay united and to direct their resentment at the Rajoy government. “The real adversary is the Spanish state, which has done everything to stop us from voting,” he said.

Polls suggest the ERC would make big gains if early elections are held, leaving Madrid staring down a regional government more fervently committed to independence.

The grassroots movement to break away from Spain has strengthened alongside the obstinacy of the central government: while in 2010 one-fifth of Catalans supported independence, by 2013 the number hovered around half, according to Catalonia’s Centre for Opinion Studies.