The US says it has full support for Ukraine as President Joe Biden met the country’s foreign minister during a visit to Poland on Saturday.
Mr Biden met with Dmytro Kuleba and Defence Minister Oleksii Reznikov alongside other senior US officials, including Secretary of State Antony Blinken and Defence Secretary Lloyd Austin.
The White House said Mr Biden updated Mr Kuleba and Mr Reznikov on US “efforts to rally the world in support of Ukraine’s fight against Russian aggression” as well as efforts to provide further defensive assistance to Ukraine.
The United States expressed “unwavering commitment to Ukraine’s sovereignty and territorial integrity,” State Department spokesman Ned Price said.
Mr Kuleba told reporters that Ukraine had received additional security pledges from the United States on developing defence co-operation.
A short time later, Mr Biden reiterated America’s fidelity to the North Atlantic Treaty’s mutual defence provisions during a bilateral meeting with Polish president Andrzej Duda.
“We take Article Five as a sacred commitment, not a throwaway — a sacred commitment that relates to every member of Nato,” said Mr Biden, who also said he believed Russian president Vladimir Putin had been counting on divisions among Nato members — “to be able to separate Eastern flank from the West, be able to separate nations based on past histories”.
“But he hadn't been able to do it — we've all stayed together,” he continued, adding that Poland has taken on a “significant responsibility” by absorbing millions of Ukrainian refugees who’ve fled their homes in the wake of Russia’s invasion.
Mr Biden said he believes the “whole world” should shoulder the responsibility of welcoming Ukrainian refugees, and compared their plight to the many migrants from South and Central America who come to the US-Mexico border seeking refuge each day.
He added that the US would “do our part relative to Ukraine” by accepting as many as 100,000 refugees.
Later in the day Mr Biden will give what his aides have billed as a major speech on “the united efforts of the free world to support the people of Ukraine, hold Russia accountable for its brutal war, and defend a future that is rooted in democratic principles”.
Biden is also scheduled to visit a refugee reception centre at Warsaw’s national stadium. More than 2 million people have fled the war in Ukraine to Poland, out of the roughly 3.8 million who have left all together.
Meanwhile, Ukraine’s President, Volodymyr Zelenskiy, said his country’s forces had “dealt powerful blows” to Russian troops, in his Friday address to his nation. On Saturday he spoke via videolink to the Doha Forum and urged the world to hike gas outputs and avoid a global energy crisis.
He also attacked Moscow, adding that their success in repelling attacks was leading the Russian leadership “to a simple and logical idea: talk is necessary”.
He added: “Russia is deliberating bragging they can destroy with nuclear weapons, not only a certain country but the entire planet.”
In Russia, former president Dmitry Medvedev warned that Moscow could launch a nuclear strike against an enemy which only had conventional weapons, “when an act of aggression is committed against Russia and its allies”, he said.
And defence minister, seen in public for the first time in two weeks, said nuclear “readiness” was a priority for Moscow.
There is growing speculation that Russia has reached a strategic turning point in the war and could abandon attempts to capture Kyiv and instead concentrate on fighting for control of the Donbas region in the southeast of the country.
A senior military official, Colonel General Sergei Rudskoi, deputy chief of the Russian general staff, said on Friday that the main objective of Moscow’s war had been “generally” accomplished, which would allow forces to focus on “the main goal, liberation of Donbas”.
In Britain, defence officials said Russia continues to besiege a number of major Ukrainian cities including Kharkiv, Chernihiv and Mariupol.
They said Russian forces are proving reluctant to engage in large scale urban infantry operations, rather preferring to rely on the indiscriminate use of air and artillery bombardments in an attempt to demoralise defending forces.
The assessment says it is likely Russia will continue to use its heavy firepower on urban areas as it looks to limit its own already considerable losses, at the cost of further civilian casualties.
There has been growing talk of Russia having committed war crimes in its assault on Ukraine and on Friday the UN said there was increasing evidence on mass graves being found in the besieged city of Mariupol.
