The Spanish government stripped the region of its autonomy after its controversial independence vote in parliament Friday, effectively taking charge of its government.
Spain has been gripped by a constitutional crisis since an independence referendum, organised by Mr Puigdemont's separatist government, was held earlier this month in defiance of a ruling by the Constitutional Court which had declared it illegal.
The Senate is expected to pass the emergency measures, which include sacking the Catalan president.
On Friday, lawmakers in the northeastern region of Catalonia passed a declaration of independence in the regional parliament.
"I'm quite sure that if Puigdemont takes part in these elections, he can exercise this democratic opposition", he said, quoted by Reuters.
Vice President Soraya Saenz de Santamaria will be Rajoy's point person in running Catalonia until the new regional election.
In a pre-recorded televised statement, Puigdemont said only the regional parliament can elect or dismiss the Catalan government, vowing to "continue working to build a free country".More news: Lynch to miss next game after appeal of suspension denied
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Catalonia's separatist leader has called on Catalans to peacefully oppose Spain's takeover, in a staged appearance that seemed to convey that he refuses to accept his firing, which was ordered by central authorities.
Puigdemont added the activation of Article 155 was a "premeditated aggression", contrary to the will of the people. Behind him there were the Catalan and European Union flags, but not the one from Spain.
Thousands celebrated Friday's declaration of independence on the streets of Barcelona, Catalonia's regional capital.
Greece also expressed concern Saturday about Catalonia's independence bid, saying it supports Spain's territorial integrity. "We continue working normally".
It's not clear at all whether a new election would solve Spain's problems with separatists in Catalonia.
Catalonia is one of Spain's richest, most distinctive regions, with a high degree of autonomy.
Spain's National Court is also investigating him as part of a sedition probe related to the banned October 1 independence referendum, when the regional police were seen as acting passively - not aggressively - to halt the vote deemed illegal by a top Spanish court. But Catalans have been divided on the question of independence.