Update: the howitzer seen in the footage has been identified as a Soviet-made 2A65 Msta-B 152 mm towed howitzer. This type is already known to be in service with Kiev forces. As of May 7, there is still no evidence that the M777 howitzers supplied by the US have actually entered service with Kiev forces.
Some of the M777 155 mm towed howitzers supplied by the West have arrived in Ukraine and entered service with Kiev forces.
On May 5, a video showing Ukrainian service members firing from a M777 howitzer on an unspecified front in the Donbass region surfaced online.
The M777 howitzer has a maximum rate of fire of seven rounds per minute with a range of up to 40 kilometers when firing Excalibur guided rounds. The upgraded versions of the howitzer are equipped with an onboard power source, satellite global positioning, inertial navigation, radio, GDB [Gun Display Unit] and SCA [Section Chief Assembly].
Kiev forces are set to receive a total of 100 M77 howitzers, 90 of which were donated by the US, four by Canada and six by Australia.
The US, Canada and Australia will also supply Kiev forces with tens of thousands of 155 mm rounds, including GPS-guided Excalibur rounds which have a CEP [circular error probable] of less than 4 meters.
Ukrainian service members are being trained on M777 howitzers in Germany, apparently out of fear of Russian strikes on military training centers in Ukraine. The Russian military have destroyed many Western weapons shipments to Kiev forces since the beginning of the special operation in Ukraine.
Kiev forces are set to receive dozens of other artillery systems from the West in the coming days, including 12 CAESAR 155 mm self-propelled howitzers from France and possibly 24 Panzerhaubitze 2000 155 mm self-propelled howitzers from the Netherlands and Germany.
The West is trying to rebuild the offensive capabilities of Kiev forces, likely to prepare them for a counter-attack against the Russian military and the armed forces of the Donetsk People’s Republic and the Luhansk People’s Republic.