Veteran Spanish right-wing politician Alejandro Vidal-Quadras has been taken to hospital in Madrid after being shot in a street, police have said.

The 78-year-old was hit in the face in a central street in the capital at about 1.30pm local time and conscious when taken to hospital, police added.

Mr Vidal-Cuadras was a long-time member of Spain's conservative Popular Party, its regional leader in Catalonia, and a European Parliament member before he broke away to help found the far-right Vox party.

He left Vox just after a failed bid to win a European seat in 2014.

The Herald: Alejandro Vidal-Quadras. File Photo Getty.

Police are investigating the shooting.

Vox president Santiago Abascal said he believed Mr Vidal-Quadras' life was not in immediate danger.

"Thank God it seems that Alejandro Vidal-Quadras is out of danger," Mr Abascal said.

Popular Party president Alberto Nunez Feijoo condemned the shooting and wished for Mr Vidal-Quadras' recovery.

Meanwhile, in a separate development in Spain, the country's Socialist Party has struck a deal with a fringe Catalan pro-independence party to grant an amnesty for potentially thousands of people involved in the region's failed independence bid in exchange for its key backing of acting Spanish Prime Minister Pedro Sanchez in forming a new government.

Socialist politician and party official Santos Cerdan announced the deal on Thursday in Brussels after sealing the agreement with the party led by Carles Puigdemont, who fled to Belgium after leading the failed 2017 independence attempt for Catalonia.

"This a political agreement and an agreement for an amnesty," Mr Cedran said.

The decision greatly boosts Mr Sanchez's chances of forming another minority left coalition government.

Mr Sanchez, a Socialist and Spain's leader since 2018, still needs the backing a small Basque party but he is likely to achieve that.

An amnesty has been the crucial part of difficult negotiations by representatives of Mr Sanchez's caretaker government to win the support of two Catalan pro-independence parties.

The backing of Mr Puigdemont's Junts (Together) and their rival Republican Left of Catalonia party, which gave its backing to Mr Sanchez last week, is vital if Mr Sanchez is to be reelected prime minister following an inconclusive national election in July.