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US President Joe Biden embarked on a four-day trip to Europe on Wednesday to meet key allies aiming to prevent Russia's war in Ukraine developing into a more catastrophic phase amid new fears Moscow could resort to chemical or nuclear warfare.
“I think it's a real threat,” Mr Biden told reporters on Wednesday when asked about the threat of chemical warfare.
Jake Sullivan, Mr Biden’s national security adviser, said the president would co-ordinate with allies on military assistance for Ukraine and new sanctions on Russia. He added that Mr Biden is working on long-term efforts to boost defences in Eastern Europe, where countries especially fear Russian aggression. The president is also aiming to reduce the continent’s reliance on Russian energy.
“This war will not end easily or rapidly,” Mr Sullivan told reporters at a White House briefing on Tuesday.
“For the past few months, the West has been united. The president is travelling to Europe to make sure we stay united.”
Mr Sullivan said Russian President Vladimir Putin’s references to nuclear weapons at the beginning of the conflict are “something that we do have to be concerned about,” adding that Mr Biden would be talking with allies about “potential responses” if the Russian leader takes that step.
Mr Sullivan’s description of Mr Biden's trip suggested that the crisis is entering a new and uncertain phase.
The president will touch down in Brussels on Wednesday night before back-to-back meetings with Nato and European leaders at the alliance's headquarters. There, the leaders are expected to announce additional sanctions on Russia.
“I think the meeting of all heads of state and government in Nato will provide us with yet another platform to demonstrate our unity, our support to Ukraine, but also our readiness to protect and defend all Nato allies,” Nato Secretary General Jens Stoltenberg told NBC’s Meet the Press on Sunday.
Mr Biden will also visit Poland, which has so far taken in more than 2.1 million Ukrainian refugees, to discuss the humanitarian crisis.
The Eastern European Nato ally, which shares a border with Russia, proposed sending peacekeepers into Ukraine, a step that Mr Biden has thus far rejected. Russian Foreign Minister Sergey Lavrov has said any western ground presence in Ukraine could lead to a war with the West.
The US and its allies for weeks have imposed a series of sweeping sanctions on Russia and sent billions of aid into Ukraine, whose city of Mariupol has been surrounded by Russian forces.
Hundreds of thousands of people in the port city have been sheltering since the early stages of the war nearly four weeks ago. Ukrainian President Volodymyr Zelenskyy said 100,000 of its residents have been cut off from food, water and medicine due to the siege.
Agencies contributed to this report