"The government was able to intervene with some measures to guarantee the correct governance of the company and the whole group," Monti said.
The prime minister had earlier promised to do "whatever necessary to clean up" Finmeccanica.
He also assured that the prosecution would do its duty in the case of Finmeccanica's jailed ex-chief executive officer Giuseppe Orsi.
"I am sure that the prosecution in this case will do its duty as in other similar cases," he told reporters.
Orsi on arrested by Italian agencies on Tuesday as part of their probe related to international corruption in a case involving the payment of bribes in the Rs 3,600 crore deal for 12 VVIP helicopters to India.
In February 2010, India had inked the deal to acquire the 12 three-engine AW-101 helicopters from AgustaWestland for IAF's elite Communication Squadron, which ferries the President, PM and other VVIPs.
The deal came under the scanner of Italian agencies after allegations of kickbacks given in India surfaced.
Finmeccanica, Italy's biggest defence contractor, appointed Alessandro Pansa as the new CEO to succeed Orsi.
Earlier, Economy Minister Vittorio Grilli had said that his ministry was working to make sure that Finmeccanica adopts a system of governance that provides management continuity, protects shareholders' interests and guarantees transparent decision-making.