MADRID — With a referendum on independence blocked by objections from Madrid, Catalonia’s leader said Tuesday that the Spanish region would go ahead next month with a nonbinding vote on secession.

In his latest act of defiance toward Madrid, Artur Mas, the Catalan leader, called off his push for a secession vote next month but announced that the regional Catalan government would instead urge its citizens to take part in a looser, nonbinding consultation on the same date. He added that his government had the right to organize such an expression of popular will and that doing so would not violate Spanish law.

“We have sufficient strength to do what we said we would do, which is to consult the people of Catalonia,” Mr. Mas said at a televised news conference. “There will be ballot boxes and papers” on Nov. 9, he added.

His alternative plan is less likely to push Spain into a constitutional crisis, even if it creates, at least for now, further political and legal uncertainty and continues to be opposed by the central government of Prime Minister Mariano Rajoy. An informal ballot would also struggle to receive the international legitimacy that Mr. Mas had hoped to achieve with a vote.