Malta is in "a democratic crisis" because of the Vitals hospitals deal, Bernard Grech said on Sunday.
"The democratic crisis is so serious that even the president of the republic spoke out," the PN leader told party faithful in San Gwann.
Students, academics, business lobbies, social partners and NGOs have also said Malta is in upheaval, he added.
For the last two weeks, Malta's political agenda has been dominated by ripples caused by the conclusion of the Vitals' magisterial inquiry.
Former prime minister Joseph Muscat, central bank governor Edward Scicluna, and Chris Fearne - who resigned as deputy prime minister on Friday - all face criminal charges as a result of that inquiry.
Robert Abela has insinuated a lack of trust in proceedings, claiming the timing of the magistrate's conclusion was deliberate and that people of interest like Muscat and Fearne were not interviewed as part of the investigation.
The PN has meanwhile called a public protest for Monday.
On Sunday Grech said the prime minister had denied there was any sort of crisis, but Fearne's resignation proved the country was in turmoil.
Fearne resigned from cabinet on Friday as he faces criminal charges over the hospitals' deal. Abela asked the deputy prime minister to stay on, but Fearne said he would not.
"Insisting that Fearne stays on proves that the prime minister does not care about good governance standards," Grech said on Sunday morning.
He added that Abela was too distracted by his own problems to manage the country well and focus on the needs of Malta's localities.
"The prime minister is distracted, isolated and put himself into a corner through the choices he made.
"Between the common good and his personal gain, Abela chooses the latter," the PN leader said.
Quoting a Facebook post by academic Andrew Azzopardi, Grech said the concession to give public hospitals to Vitals was "a direct attack on people's quality of life".
Besides showing how the government is "defrauding" and "stealing" from the people, the PN, its MPs, candidates and activists are focused on the people's needs, he said.