The President of Catalonia Artur Mas and his ruling Convergence and Union (CiU) party are "already exploring other possibilities (aside from the vote)" if Spain's Constitutional Court vetoes the poll, an unnamed figure high up in the party told the centre-left daily.
Mas has been pushing hard for the November 9th vote responding to pressure from a growing band of Catalan nationalists to stage the poll.
Even a declaration from the central government in Madrid that such a poll would be illegal has failed to quell his apparent enthusiasm.
"There is no plan B," Mas told reporters after a July meeting with Spanish Prime Minister Mariano Rajoy, affirming the vote would go ahead.
Recent suggestions from Mas' deputy that the poll could be postponed if the Constitutional Court vetoed the move were also dismissed, with Mas saying he wouldn't budge on the date.
But the new declarations from within the party suggest Mas is willing to be flexible.
The Catalan government is currently finalizing details of the planned vote, with the regional government expected to pass a bill allowing for it to take place in mid-September, or after the region's September 11th National Day, when pro-independence fervor is at its peak.
But the Spanish Prime Minister is likely to immediately seek a veto from the Constitutional Court as soon as this happens.
"In this scenario, we won't go to the polls, because it would be too easy for our opponents," the CiU insider told El País, arguing that the region's opposition parties will call for their supporters to abstain.
"We want 80 percent participation and not 50 percent participation with thousands of 'nos'," he added.
Mas was now seeking the maximum consensus and all options were on the table. the CiU party figure said. Among these options was the possibility of bringing forward regional elections which could act then as a plebiscite on the question of independence.
Catalonia's nationalist opposition ERC party responded on Tuesday by saying it would not backtrack on the November 9th date.
Pacts had to be honoured, said party leader Oriol Junqueras, a reference to a deal between the ERC and the CiU to stage the referendum.
Support for independence in Catalonia was about 45 percent in April, according to the regional government's polling.
Proud of their distinct language and culture and fed up after five years of stop-start recession, many of the 7.5 million people in Catalonia want to redraw the map of Spain, saying they feel short-changed by the central government which redistributes their taxes.
On Sunday, an Irish politician argued Spain would block an independent Scotland's entry into the European Union.
"Spain will not want to create the precedent in another member state of a nation/region deciding to leave and join the EU in their own right," said Ruairi Quinn, who headed up the EU's Economic and Financial Affairs Council in 1996.