After telling Italian premier Matteo Renzi that Western sanctions imposed over Russia's actions in Ukraine would cost Italian companies a billion euros, Putin spent 50 minutes chatting to the Pope at the Vatican.
A Vatican statement said the pontiff had urged the Russian leader, and other parties to the Ukraine conflict, to make a "sincere effort" for peace.
"The holy father stressed that there has to be an important and sincere effort to achieve peace (in Ukraine)," the statement said.
"There was agreement on the importance of rebuilding an atmosphere of dialogue and that all the parties commit to applying the Minsk (ceasefire) accords."
Speaking two days after the G7 threatened tougher measures against Moscow, Putin told a press conference in Milan that many contracts signed by Italian firms had been stalled by the sanctions and may have to be torn up.
"Italian companies missed out on a billion euros," he said. "They could have given their enterprises work, created jobs. That didn't happen because of the sanctions."
Putin also said he was convinced sanctions would not be sustained indefinitely. "I count on the fact that...sooner or later, we will get away from the restrictions that we are encountering today."
G7 'just a club'
He took a swipe at the G7 group of leading industrial nations - made up of Britain, Canada, France, Germany, Italy, Japan and the United States - describing it as "not an organisation, just a club."
Renzi struck a markedly conciliatory tone by stressing that the world wanted Russia back on board to help resolve problems in places such as Iraq, Syria and Libya.
Active Russian support for efforts to promote peace in Ukraine would "allow us to push the one element of divergence between us off the table," Renzi said in comments that contrasted sharply with US President Barack Obama's description this week of Putin as trying to relive the glories of the Soviet empire.
The Italian leader said Putin had agreed that the Minsk agreement governing a shaky ceasefire in Ukraine had to be the "guiding star, the compass, the reference point" for resolving the crisis.
The tough line adopted by the G7 reflected concern about a recent flare-up in fighting in eastern Ukraine, where the West accuses Russia of providing game-changing military support to pro-Moscow rebels who control parts of two Russian-speaking regions.
Ukraine this week said Russian aid had allowed separatist forces in the east to establish a 42,500-strong fighting force.
Putin says any Russians fighting alongside the rebels are volunteers "answering a call of the heart".
Italy has long had an important economic relationship with Russia and political ties were sufficiently close prior to the eruption of the Ukraine crisis for Russia's Baltic neighbours to object to an Italian, Federica Mogherini, being named the EU's foreign policy chief last year amid claims she would be too soft on Moscow.
Italy is Russia's third-biggest trading partner after China and Germany with deals between the two countries worth just over €30 billion ($33.9 billion) last year.
Still a player?
Analysts say Putin's meetings with Renzi, recently-elected president Sergio Mattarella and the pope will play well to his domestic audience, giving the impression he remains a player on the global stage.
The Vatican has been criticized, notably by the Rome-aligned Greek Catholic minority in Ukraine, for failing to overtly criticise Moscow's actions in Ukraine.
But the crisis has also stalled a historic rapprochement between the Vatican and the Russian Orthodox church, dashing hopes the Argentinian pontiff could become the first pope to visit Moscow since the 11th Century schism between Eastern and Western Christianity.
After his visit to the Vatican, Putin is expected to call on long-standing friend Silvio Berlusconi, the media tycoon and disgraced former Italian prime minister.
The two men, who have regularly holidayed together, last met in Milan in October, carousing together until 3am while Berlusconi was still serving a community service order for tax fraud.