England defender Stones joined Serie A champions Inter Milan earlier this month after a decade and several titles at Manchester City.
The veteran adds a wealth of experience to Inter who are seeking to defend their league title under Chivu who believes that Stones will boost their chances of fending off the likes of AC Milan, Napoli and Roma at the top of the table.
“The squad is competitive, but you always need key players who can make you take that quality leap and allow you to stay aligned with this club's ambitions."
"It's special to face a great team like City. Obviously, we're not at 100% physically, but we'll do our best. The squad is competitive, but there's always a need for important players. Stones raises the bar. We are keeping an eye out for opportunities.
"I have always asked to raise the bar and bring in important players who want to be part of this wonderful group. We are paying attention to opportunities to raise the level that these lads have maintained for many years."
Stones said he had "lived all my dreams out" after helping City to every trophy possible and he will now help Inter chase their 22nd title as they kick off their title defence against newly promoted Monza on Saturday, 22nd August.
The 32 year old managed just nine Premier League appearances last campaign after suffering from thigh and calf issues but the defender now looks to be back at full fitness.
Inter Milan face Manchester City in a preseason friendly later this month as Stones returns to his former side.