MADRID - Spain’s acting Prime Minister Pedro Sanchez rejected conditions set out by center-right leader Albert Rivera to back him in a vote to form a government, a Socialist party source said on Monday.

Rivera said earlier he would encourage a fellow right-wing leader to jointly abstain to facilitate Sanchez’s bid to form a government, some five months after inconclusive elections, provided the Socialist acting prime minister fulfilled a series of demands.

A source in Sanchez’s caretaker government said he had asked both right-wing parties not to vote against his bid, and none of Rivera’s conditions should impede his receiving a mandate to form a government.