STORY: Air raid sirens blaring in Ukraine's capital on Monday (February 20), at the same time that U.S. President Joe Biden landed there for a surprise visit, and just days before the one year anniversary of Russia's invasion.

Biden was in St. Michael's Cathedral with President Volodymyr Zelenskiy as it happened.

There were no reports of Russian missile or air strikes in Kyiv, but it underlines the grinding nature of the war, which has seen no major changes on the ground for months.

Biden is using the trip to announce $500 million in new military aid to Ukraine, including air defense radars, weapons for taking out armored vehicles, and artillery ammunition.

Allies have recently voiced concern that Ukraine may be burning through ammo faster than the West can supply it.

ZELENSKIY: "We also discussed the issue of long-range weapons, and the weapons that can be supplied to Ukraine, which were not there before, and this is very important.

BIDEN: "Freedom is priceless. It is worth fighting for as long as it takes. And that's how long we're going to be with you, Mr. President. For as long as it takes.”

Biden made no mention of donating Western fighter jets at their joint press conference, which Ukraine has been pushing for, and if granted would be another upgrade in firepower after the recent pledges of modern Western tanks.

Zelenskiy did say though, that he and Biden discussed long-range weapons. This could be war planes or better missile systems.

So far the West has resisted both of these on fears that they would be used to strike deep into Russia and even further escalate the war - although some members of congress have told Reuters that they believe consensus is building on Capitol Hill to provide Ukraine with American F-16 fighter jets.

Meanwhile, as Biden visits Ukraine, China's foreign minister is heading to Russia. China has so far remained neutral in the war, despite its close relationship to Moscow. The West fears it could begin supplying Russia with its own weapons.