LUXEMBOURG - Britain, France and Germany aim to persuade the European Union on Monday to condemn Russia's devastating air campaign in Syria and pave the way for imposing more sanctions on the regime of President Bashar Assad.
The bloc also plans to continue pushing for humanitarian aid to reach the besieged city of Aleppo.
Struggling to help end Syria's war, the EU is stepping up efforts to support the United States in its bid to stop the bombing of eastern Aleppo, where 275,000 people are trapped.
But it is split over strategy towards Russia, its biggest energy supplier.
EU foreign ministers meeting in Luxembourg on Monday after the United States held weekend talks in Lausanne and London will voice their harshest criticism yet of Russian air strikes in eastern Aleppo that have destroyed hospitals and targeted an aid convoy. EU leaders meet on Thursday to discuss further steps.
"It is vital that we keep that pressure up," British Foreign Secretary Boris Johnson said following his meeting in London on Sunday with US Secretary of State John Kerry, before heading to Luxembourg for the EU meeting.
"There are a lot of measures we're proposing, to do with extra sanctions on the Syrian regime and their supporters, measures to bring those responsible for war crimes to the International Criminal Court," said Johnson. The United States is also considering additional sanctions.
A draft of the diplomatic statement to be delivered on Monday says EU ministers will condemn the "catastrophic escalation" of the Syrian government offensive to capture the eastern zone of Aleppo, where 8,000 rebels are still holding out against Syrian, Russian and Iranian-backed forces.