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Emmanuel Macron said Moscow's offer of humanitarian corridors out of besieged Ukrainian cities amounted to unbearable cynicism.
The French Foreign Minister Jean-Yves Le Drian criticised Russia’s offer of humanitarian corridors for Ukrainian civilians as a “trap” that could possibly lead to more bombing in Ukraine.
Le Drian said in such cases Russia’s proposal of establishing humanitarian corridors actually led to more bombings after negotiations failed.
“We must not fall into traps,” Mr Le Drian added.
With fighting escalating about five million refugees could flee Russia’s invasion of Ukraine and arrive in EU member states, EU foreign affairs chief Josep Borrell warned.
The UN’s refugee agency said on Monday that more than 1.7 million people have already fled the conflict in Ukraine, with Polish border guards saying they had registered 964,000 refugees by Sunday.
Mr Borrell also said there should be more scrutiny of EU aid spending in countries that have supported Russia diplomatically or have not criticised Moscow's invasion of Ukraine.
“We must prepare to receive around five million people … We must mobilise all the resources of the EU to help those countries receiving people,” Mr Borrell said as he arrived for a meeting of EU development ministers in Montpellier, France, on Monday. “We will need more schools, more reception centres, more of everything.”
Refugees have also arrived in Hungary, Slovakia, Moldova and Romania.
The Red Cross said the fighting in Ukraine “is shaping up to be one of the biggest humanitarian emergencies in Europe for years to come".
“The displacement and needs are massive and will likely grow, both inside and outside of Ukraine,” said Francesco Rocca, president of the International Federation of Red Cross and Red Crescent Societies.
Hundreds of civilians have been killed and thousands wounded in the fighting.
Mr Rocca said that millions of people still in Ukraine are currently “in desperate need of safe drinking water and food".
“With roads impassable, and electricity and water supplies cut off, people desperately need emergency medical care, medicine, clean water and shelter,” he said.
“Without urgent action to protect these services, large-scale humanitarian impacts are expected.”
Amid a flurry of diplomatic activity among senior figures in the EU and Nato, US Secretary of State Antony Blinken was in Lithuania on Monday as part of a tour of Baltic Nato member states.
“Unfortunately, the worsening security situation in the Baltic region is of great concern for all of us and around the world,” Lithuanian President Gitanas Nauseda told Mr Blinken.
“Russia’s reckless aggression against Ukraine once again proves that it is a long-term threat to European security, the security of our alliance.”
Mr Blinken also traveled to Riga, Latvia before visiting Tallinn, Estonia, on Tuesday.
Mr Blinken sought to reassure Nato's eastern members of their security in the event Russia chooses to expand its military operations.
“We are bolstering our shared defence so that we and our allies are prepared,” he said, stressing that the US commitment to Nato's mutual defence pact is “sacrosanct".
“We will defend every inch of Nato territory if it comes under attack,” Mr Blinken said. “No one should doubt our readiness, no one should doubt our resolve.”