Kyiv, Ukraine - A shipment of new US military aid has arrived in Kyiv, officials announced on Saturday, upping the ante of an already tense situation in which Russia is accused of being poised to invade its fellow former Soviet republic.

A US cargo plane landed at an airport in the capital Kyiv during the night, the US embassy there announced on Twitter on Saturday.

On board was 90 tons "of lethal aid, including ammunition for the front line defenders of Ukraine." This support had been ordered by President Joe Biden.

The embassy published pictures showing the plane being unloaded. It was the first of several deliveries, it said.

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"The shipment – and 2.7 billion [dollars] since 2014 – demonstrates US commitment to helping Ukraine bolster its defenses in the face of growing Russian aggression," the embassy tweeted.

Russia had repeatedly called on Ukraine not to arm itself further because this would fuel military tensions and could encourage the country to attack, for example, the Donbass region in the east of the former Soviet republic in order to take back the pro-Russian breakaway provinces of Luhansk and Donetsk there.

Russia's Foreign Minister Sergei Lavrov and his US counterpart Antony Blinken only met on Friday for crisis talks in Geneva.

Most recently, the Kremlin had sharply criticized the delivery of light anti-tank weapons from Britain to Ukraine.

The Baltic states Estonia, Latvia, and Lithuania now also want to send US-made anti-tank missiles and anti-aircraft systems to Ukraine.

Tensions around the simmering Ukraine conflict have been rising as the US insists that Russia intends to invade its neighboring country. Moscow has already rejected the accusations several times.

Against this backdrop, reports emerged on Saturday that family members of embassy personnel were being told to leave Ukraine. Some reports said US family members had been told to leave by Monday.

The State Department said on Saturday that it had no comment on the matter, but added that US citizens living in Ukraine should not expect an evacuation effort organized by the US should the situation change.

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The department noted that commercial flights are available for those seeking to leave Ukraine.

There were also reports in US media about Russia pulling out its diplomatic staff and dependents, which Moscow denied. "The Russian embassy in Kyiv is working routinely," according to officials there.