MADRID - Spain's acting Prime Minister Pedro Sanchez on Tuesday said he will start meeting with other political parties to reach an agreement that will not only confirm a Socialist-led government but last a full four-year term.

"I'm ready to work to form as soon as possible a progressive coalition government with enough support to ensure the stability the country needs," he told reporters on Tuesday after King Felipe mandated him to seek investiture in the lower house.

To reach the threshold of votes needed to stay in office, Sanchez will have to woo Catalan and Basque parties, some of which are seeking their region's independence from Madrid.

One of the demands made public by the hardline Junts per Catalunya is a blanket amnesty for Catalan separatists facing legal woes over the region's failed independence bid in 2017. Sanchez's turn comes after Alberto Nunez Feijoo of the conservative People's Party last week fell short of the majority required to become prime minister.

(Reporting by David Latona; Editing by Inti Landauro and Aislinn Laing)