Spain's prime minister and Catalonia's regional leader said their positions on independence remained "very far apart," after restarting talks on Wednesday aimed at improving ties damaged by the northeastern's region failed 2017 separatist bid.

Prime Minister Pedro Sanchez said his visit to Barcelona and the reopening of a dialogue sent a powerful message that his government wants to improve relations, although he insisted that a flexible time frame was needed to reach any agreement as he laid out over 40 issues of potential accord.

But he stressed his position regarding Catalonia's request for an authorized independence referendum remained unchanged.

"The Spanish government will always respect democratic legality, the constitutional order", Sanchez told reporters after meeting Catalonia's head Pere Aragones, whose Esquerra Republicana de Catalunya party was instrumental in enabling his Socialist-led minority government to take office in 2020.

Sanchez is again seeking the support of left-wing separatists Esquerra to pass the 2022 budget in coming weeks, although he said the issue was not discussed.

Esquerra had said resuming the talks - interrupted since the COVID-19 pandemic struck in early 2020 - was an essential precursor to negotiations on the budget. After meeting Sanchez, Aragones said the talks could facilitate the party's support.

In what he said was a goodwill gesture, Sanchez in June pardoned nine Catalan separatist leaders who were sentenced to lengthy prison terms for their role in the unauthorised 2017 referendum and short-lived declaration of independence, which was Spain's worst political crisis in decades.

"Our proposal is an amnesty and a referendum," Aragones said, referring to the roughly 3,000 separatists who pro-independence parties say face open legal investigations while calling the pardons a first step in the right direction.

Signalling divisions in the separatist camp, the junior party in Catalonia's governing coalition, Junts, did not participate in Wednesday's talks.

(Reporting by Joan Faus; Editing by Nathan Allen and Angus MacSwan)