A summit of more than 50 European and Asian countries in northern Italy offered the backdrop to the most determined diplomatic push in months to end the biggest crisis in the relationship between Russia and the West since the end of the Cold War.

The United States and the European Union slapped sanctions on Russia after its annexation of Crimea and its alleged fomenting of unrest in eastern Ukraine. This has prompted countermeasures from Moscow and fuelled mutual distrust.

“We care very much about the possibility to involve again Russia in the international situation,” Italian Prime Minister Matteo Renzi said in Milan, on the sidelines of the two-day Europe Asia Meeting (ASEM).

“I think in this moment of very hard crisis around the world, the role of Russia could be very important,” Renzi said, listing the challenges of Ebola, Islamic State terrorism, and conflicts in Syria, Iraq and Libya.

He spoke after breakfast talks between Russian President Vladimir Putin and his Ukrainian counterpart Petro Poroshenko, describing them as “a step ahead” in efforts to resolve the Russia-Ukraine conflict, which broke out earlier this year.

“Vladimir and Petro discussed very clearly, very frankly,” Renzi said. “It was a breakfast without breakfast, because nobody drank Italian coffee, nobody left their chair to share milk or coffee,” he quipped, conveying the intensity of the meeting.

The EU’s heavyweights - German Chancellor Angela Merkel, French President Francois Hollande, British Prime Minister David Cameron, European Council President Herman Van Rompuy and European Commission President Jose Manuel Barroso - also sat at the negotiating table.

Struggling with a flagging economy, the EU would have a strong interest in resuming full trade ties with Russia, and avoid any escalation in the Ukrainian crisis which could jeopardise Russian gas deliveries to Europe in the upcoming winter season.

Hollande said tensions “weigh” on the Ukrainian population, on Russia, on Europe and on the entire world, because of their repercussions on global security, economic growth and the stability of financial markets.

Russia could do with a detente, since its economy is suffering from a steep currency depreciation linked to the impact of sanctions and to falling world prices for oil, a key national export.

However, Italian diplomatic sources acknowledged that negotiations on defusing the Ukraine crisis would prove “difficult”, amid not-too-encouraging signals coming from German and Russian sides.

“So far, I cannot see any breakthrough here,” Merkel said, before entering into a new round of talks with Hollande, Putin and Poroshenko, on the question of using drones to control the Russia-Ukraine border.

Putin’s office also admitted that  talks between him and Merkel had revealed “serious differences in views on the source of Ukraine’s domestic conflict, as well as root causes for what is happening there today”.

Cameron, whose country is usually hawkish towards Moscow, warned the Russian leader that he could expect no thaw in relations unless the Kremlin took decisive steps to change the situation in Ukraine.