The President cannot resolve the current political crisis, his office said in a statement on Friday.
There was no legal or constitutional basis for him to intervene, the statement added.
Among others, several Nationalist MPs have said they would boycott the Republic Day parade, reception and granting of honours by the President because of the presence of Prime Minister Joseph Muscat.
Former Opposition leader Simon Busuttil commented that he could not understand how the President was proceeding with this event as if it was business as usual.
"In light of requests for the President to take measures, which, according to some, are allowed by the Constitution, in order to solve the current political situation, it has to be said that the Constitution does not provide the President with any additional powers to the ones he has already exercised."
The President could not act in breach of the Constitution, his office said.