The parties -- which form an absolute majority in the Catalan parliament -- have been negotiating for weeks over who to pick as candidate for the regional presidency as Catalonia's sacked leader Carles Puigdemont is in self-exile in Belgium.
Puigdemont wants to govern Catalonia remotely but Spain's Constitutional Court has made his appointment conditional on his physical presence in regional capital Barcelona -- and he faces arrest if he returns over his role in the attempt to break from Spain.
"A deal is imminent," said Carles Campuzano of Puigdemont's PdeCAT party on Spanish radio late on Monday, as Catalonia remains without a regional government and under Madrid's direct rule following a failed declaration of independence on October 27th.
Asked whether Sanchez, head of the ANC, a hugely influential pro-independence citizens' group, was being considered as candidate for the Catalan presidency, he said: "This is an option that is being worked on."
According to Spanish media, Puigdemont would take on a "symbolic" role from Belgium.
Leading from jail?
But choosing Sanchez, 53, is likely to cause further problems as he has been in prison for more than four months, charged with sedition over his role in the secession attempt.
He is accused of encouraging a major protest in September as Spanish police raided the Catalan administration's economic offices in the run-up to a banned independence referendum.
The October bid to break from Spain prompted Prime Minister Mariano Rajoy to sack the region's government, dissolve its parliament and call snap elections in December.
Sanchez, who was second on Puigdemont's Together for Catalonia list in the polls, was elected as a regional lawmaker.
If he is chosen as candidate to lead Catalonia, it will be up to a Supreme Court judge to allow him out of jail to be officially appointed at a parliamentary session in Barcelona.
This in theory is possible, even if the judge previously refused such a request made by jailed, former Catalan vice president Oriol Junqueras.
And even if Sanchez was allowed to go to the session, he would then have to govern from jail and ask to be freed to attend other meetings.
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