The Spanish government has given Catalonia three days to declare whether it will try to break away from Spain or not, moving ever closer towards imposing direct rule on the northeastern region.

Madrid had given a deadline of 9:00 a.m. London time Monday for an official response from Catalonia, hoping to receive a clearer indication on whether it had declared independence or not.

However, when a letter arrived from Catalan leader Carles Puigdemont just two hours before the deadline, it failed to offer any confirmation either way.

Spain's Deputy Prime Minister Soraya Sáenz de Santamaría told a news conference later on Monday that Puigdemont had not made his position clear and the government would give him until Thursday morning to give a formal confirmation.

"It's not a hard question we have asked, it's not a hard question to respond to," she said.

"10:00 a.m. (local time) on Thursday is the deadline," she added. "We are very disappointed he hasn't given a yes or no answer to the question we asked."

"He is prolonging the situation," she said.