On the eve of the talks gathering representatives from 50 countries, President Volodymyr Zelensky had urged Western allies to send more fighter jets and long-range missiles to help repel Russian troops.

"Our support for the forces of freedom in Ukraine holds strong and true," Austin said, as he began the discussions, a year after the format of talks between defence leaders began to coordinate aid for Ukraine.

"At today's contact group meeting, we'll focus on three key issues -- air defence, ammunition and enablers," said Austin, referring to logistics and other support.

Zelensky had asked for NATO's help to "overcome the reluctance" of some member states in providing long-range rockets, modern fighter jets and armoured vehicles, putting his request directly to the alliance's chief Jens Stoltenberg, who on Thursday made his first visit to Kyiv since Russia's invasion last year.

In Ramstein, Stoltenberg acknowledged the need to discuss "new platforms" of support with the battle now in its second year. But he also underlined the need to ensure that already supplied weapons continued to work.

"This is now a battle of attrition, and a battle of attrition becomes a war of logistics," Stoltenberg said, adding, "maybe it's also a bit more boring but the logistics is extremely important".

The Ramstein gathering drew anger from Moscow, with the Russian foreign ministry saying the allies' action for Ukraine "confirms their direct involvement in the conflict and participation in the planning of military operations".

Kremlin spokesman Dmitry Peskov also accused NATO of trying to "absorb and drag Ukraine into the alliance", showing Russia was right to "launch this operation" to ensure its security.

- Air defence -

The Ramstein meeting began with "fruitful" talks on military aid between Kyiv's representatives and their US counterparts, Ukrainian Defence Minister Oleksiy Reznikov said on Twitter.

NATO members have forwarded Soviet-era fighter jets to Ukraine but have held off sending more modern models such as the US-designed F-16 sought after by Kyiv.

They have however provided Ukraine with anti-air missiles, with Kyiv earlier in the week saying it had received the first shipment of Patriots, seen as one of the most advanced US air defence systems.

The kit has been among Kyiv's key demands from Western allies as it looks to defend itself from Russian missile attacks and roll back Moscow's invasion.

In eastern Ukraine's Lugansk region, AFP saw a group of servicemen using British-supplied artillery several kilometres from Russian positions.

One hauled shells to the UK-made gun from a nearby cache, while others set coordinates and loaded the barrel before the final order to "Fire!".

"There are the planned targets that we work on. And some appear unexpectedly, for example, to repel an assault when the enemy advances," said Bogdan, a 40-year-old Ukrainian serviceman from the embattled town of Bakhmut.

"The enemy is using few military vehicles. Infantry, which is what the enemy has plenty of, goes forward," he said.

- NATO bid -

During Stoltenberg's visit to Kyiv, the NATO chief was also pressed on allowing Ukraine to join the alliance, but he stressed it was not an immediate priority.

"All NATO allies have agreed that Ukraine will become a NATO member, but the main focus now is of course on how to ensure that Ukraine prevails," he said on Friday at Ramstein.

"Without a sovereign, independent Ukraine, there is no meaning in discussing membership," he said.

The NATO chief also said the alliance was examining a "multi-year programme to help Ukraine transition from Soviet-era equipment standards (and) doctrines to NATO standards and doctrines."

"We need to ensure that Ukraine has the military strength ... that deterrence to prevent new attacks because you have to remember that the war didn't start in February" last year but with Russia's 2014 annexation of Crimea.

Over a year into its invasion, Russia struck Kyiv with drones overnight in the first such attack for almost a month, although city officials reported no casualties.

Moscow suffered a setback with one of its fighter jets losing munitions over Belgorod near the Ukrainian border.

Local authorities reported a blast that injured two people and left a huge crater in the Russian city.

The region of Belgorod has been repeatedly shelled since Russian President Vladimir Putin sent troops to Ukraine in February 2022.