The EU and United States under then president Barack Obama imposed sanctions on Moscow over its 2014 annexation of Crimea.
The EU and United States under then president Barack Obama imposed sanctions on Moscow over its 2014 annexation of Crimea and fighting in eastern Ukraine between government forces and pro-Russia rebels.
But it is as yet unclear whether Obama's successor Donald Trump, who is under fire domestically over allegations that Russia meddled to aid his election campaign last year, will maintain these sanctions.
"Since our last G7 summit in Japan, we haven't seen anything that would justify a change in our sanctions policy towards Russia," Tusk, who coordinates policy for the EU's 28 leaders, told reporters in Sicily.
"I will appeal to the other G7 leaders to reconfirm this policy," he added before the latest summit of seven leading industrialised nations kicked off in the town of Taormina, with Trump one of four leaders new to the G7 party.
Tusk already met with Trump on Thursday in Brussels, and said that while both sides did not have a "common position about Russia", they appeared to be on the same line where the Ukrainian conflict is concerned.
In March, the US State Department said Washington's "Crimea-related sanctions will remain in place until Russia returns control of the peninsula to Ukraine".
But Trump's chief economic advisor Gary Cohn appeared to cast doubt on this Thursday.
"Right now, we don't have a position," he told reporters on board Air Force One as Trump headed to Sicily, the final stop of his first foreign trip as president.
"He's got many options," Cohn added, without giving further details.
In his press conference, though, Tusk was optimistic, saying he expected that "the G7 will demonstrate unity regarding the conflict in Ukraine".