He did not refer to the violence with which police cracked down on voting day but said "nobody can be proud of the image" Spain projected, adding the only ones to blame were the Catalan leaders.
Those who opposed the referendum had said they would boycott the vote.
Here is the status of the standoff between the affluent, industrial region of Catalonia and the central Spanish government in Madrid.
He has given Catalonia's separatist leader five days to clarify whether or not he has declared independence.
He said his party and Rajoy's People's Party had agreed to renegotiate the laws that provide certain areas of autonomy to Spain's 17 regions, including Catalonia.
Rajoy could choose to trigger constitution article 155, which allows Madrid to impose control over its devolved regions - an unprecedented move many fear could lead to unrest.
The European Union has also shown no interest in an independent Catalonia, despite an appeal by Mr Puigdemont for Brussels to mediate in the crisis. He said this includes the use of Article 155 of the Spanish Constitution, which would allow the central government to take control of the governance of a region "if the regional government does not comply with the obligations of the Constitution".
The Catalan crisis has deeply divided the region itself as well as the Spanish nation.
Catalan separatists remain furious at the actions of Spanish national police and Guardia Civil when they sought to disrupt the independence referendum, which saw officers raiding polling stations, beating voters and firing rubber bullets at crowds.
The Catalan leader, who commands only a slim majority in the Catalan parliament, had come under intense pressure from moderates in his ranks to try to avoid giving Madrid reasons to announce direct rule.
The EU today urged "full respect of the Spanish constitutional order", with European Commission vice-president Valdis Dombrovskis saying the bloc was following developments "closely". Tusk said he had asked "Prime Minister Rajoy to look for a solution to the problem without the use of force".
Pedro Sanchez, leader of opposition Socialist Party, said party and government agreed to address possibilities of constitutional reform in order to end crisis.
Rabat rejected Catalonia's secession bid and expressed its commitment to Spain's sovereignty, national unity and territorial integrity, according to statement issued Wednesday by Morocco's Ministry of Foreign Affairs.