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Italian Prime Minister Mario Draghi and US President Joe Biden stressed transatlantic unity in the unprecedented western response to Russia's invasion of Ukraine at a White House meeting on Tuesday.
“The ties between our two countries will always be strong and, if anything, this war in Ukraine has made them stronger,” Mr Draghi said.
Russian President Vladimir Putin “thought he could divide us — he failed”, Mr Draghi told Mr Biden. “We stand together.”
While calling out Russia's “butchery” in Ukraine, Mr Draghi said it was time to “think deeply” about arranging a ceasefire.
“People want to think about the possibility of bringing a ceasefire and start engaging in credible negotiations,” he said.
Mr Biden, who hosted Mr Draghi in the Oval Office, also praised western unity, saying in comments while reporters were present that “Putin believed he could split us, but we've all stepped up”.
Despite Italy's dependence on Russian gas and Rome's traditionally friendly ties with Moscow, Mr Draghi's government has been a staunch supporter of efforts to punish Russia for its assault on Ukraine.
Along with western allies, Rome has sent weapons to support Kyiv, although there is increasing unease about the move within Mr Draghi's national unity government.
Mr Draghi has also pledged support for any European Union sanctions on Russia's energy sector despite the risks — 40 per cent of Italy's natural gas imports come from Russia.
The EU is currently debating a phased ban on Russian oil imports, although this move would not touch Moscow's huge gas exports.
Germany has ruled out an immediate embargo on all Russian energy, especially natural gas, although it aims to end Russian oil imports by the end of this year.
The meeting at the White House comes before crucial G7 and Nato summits in Europe next month.
Beyond Ukraine, the leaders were expected to discuss the global economy and climate change.
Mr Biden, who has made a priority of repairing tattered US-EU ties after former US president Donald Trump left the White House, told Mr Draghi that “a strong European Union is in the interests of the United States”.
“It's good for everyone,” he said.
Mr Draghi has particularly close ties with the US.
He did his doctorate at MIT and worked for both the World Bank and US investment bank Goldman Sachs. He was also president of the European Central Bank for eight years.
While in Washington, Mr Draghi will receive an award from the Atlantic Council for distinguished international leadership.
It is scheduled to be presented by US Treasury Secretary Janet Yellen at a ceremony on Wednesday.