Live updates: follow the latest news on Russia-Ukraine
US President Joe Biden's administration asked Congress at the weekend for $10 billion in military, economic and humanitarian aid to Ukraine — an amount that would dwarf the $1bn in assistance Washington has already provided to Kyiv over the past year.
Speaker Nancy Pelosi said in a letter on Sunday that the House of Representatives would consider the Ukraine emergency aid request in the government funding bill that Congress will vote on later this week.
The Biden administration had initially wavered on sending Ukraine lethal military assistance, but the US calculus changed in December after Russia began amassing troops on the Ukrainian border in a precursor to the invasion.
The Biden administration first gave Ukraine a $60 million security assistance package in August, which included Javelin anti-armour systems.
The non-lethal aid also included vehicles, radars, electronic equipment such as radio systems and medical supplies.
That hardware was not fully delivered to Ukraine until the following November.
That same month, Russia began massing troops on the border and the Biden administration subsequently authorised another $200m in security aid.
At least 90 tonnes of US equipment from that package, which included lethal aid, arrived in Ukraine in January.
The Washington Post reported last week that the US had begun in December to equip Ukrainian troops with equipment for urban combat, which reportedly includes shotguns, shoulder-launched rocket launchers, grenade launchers and specialised suits for handling unexploded bombs.
When Russia’s invasion of Ukraine began in earnest in February, the Biden administration used its existing authorities to provide another $350m in military aid.
With the invasion well underway, the US has sought to expedite delivery of its latest military aid package and much of that equipment began arriving in recent weeks.
The US managed to deliver 70 per cent of that package — including Stinger surface-to-air missiles from US stockpiles located in Germany — within five days by successfully making use of supply lines to the Ukrainian military through Poland and Romania.
The Nato alliance - in pictures
A February Congressional Research Service report also notes that the US has reportedly sent Ukraine Mi-17 helicopters that had originally been scheduled to go to Afghanistan before the Taliban takeover last year.
The US and Nato have so far provided Ukraine with more than 17,000 anti-tank weapons, including additional Javelin missiles.
Ukrainian President Volodymyr Zelenskyy has welcomed the US assistance but has repeatedly stressed that more must be done.
In addition to calling for sanctions on Russia’s energy sector as well as instituting a no-fly zone over Ukraine, he has also asked Nato to provide his embattled country with fighter jets.
US Secretary of State Antony Blinken said on Sunday that Washington’s Nato allies have a green light to provide Ukraine with fighter jets.
“We're talking with our Polish friends right now about what we might be able to do to backfill their needs if in fact they choose to provide these fighter jets to the Ukrainians,” Mr Blinken said in an interview on CBS.