The United States on Thursday announced $675 million in additional military equipment for Ukraine, as it said allies' efforts in bolstering Kyiv were now visibly paying off on the battlefield.

Hosting a new round of talks with partners in Germany, US Defense Secretary Lloyd Austin said Kyiv was now not only resisting Russian invaders, but is mounting a counter-offensive in the south.

"It's fitting that we're meeting back here at Ramstein," he said, referring to the US airbase in western Germany where the first of the "Ukraine Defense Contact Group" meetings on coordinating armaments support for Kyiv took place.

"Now, we're seeing the demonstrable success of our common efforts on the battlefield," he said, stressing that allies are in it "for the long haul".

The meeting came hours after Ukraine President Volodymyr Zelensky said his forces had recaptured several settlements in the northeastern Kharkiv region from the Russians.

Ukraine has also claimed it had retaken several villages in the south of the country where it has been waging a counter-offensive since last week.

Kyiv has repeatedly urged its allies for more heavy weapons as it pursues its pushback. Prime Minister Denys Shmygal reiterated the request when he visited Germany on Sunday.

'Significant consumption'

Among the issues to be raised at Ramstein are the challenges of producing and restocking arms, as "there is a significant consumption of munitions in the conduct of this war that's occurring in Ukraine", said top US General Mark Milley.

The aim would be to look at what stocks are available in which countries and what would need to be sourced from industry, he said.

Artillery is proving decisive in the war and projectiles of all sorts are in huge demand.

With Ukraine and Russia fighting a war of attrition of munitions, stocks are similarly a crucial factor.

Having already exhausted all its Russian-made armaments, Ukraine is now entirely dependent on Western military support.

Russia, under heavy sanctions, is meanwhile turning to North Korea for huge quantities of rocket and artillery shells, said Washington.

'More effective'

The United States has been Ukraine's biggest armaments supplier.

Its latest package would include 105mm howitzers, precision-guided GMLRS rockets and artillery ammunition.

It comes on top of $13.5 billion worth of various weapons, including anti-tank Javelin missiles and shells compatible with NATO's artillery systems.

Among the most efficient weapons sent lately by Washington are the HIMAR multiple rocket launch systems, paired with GMLRS rockets that can reach targets up to 80 kilometers (50 miles) away.

But Kyiv is seeking ATACMS -- precision-guided, medium range tactical missile that can be launched by the HIMAR systems and which are capable of striking at 300 kilometers.

The United States has so far refused, as it fears the missiles could land in Russian territory, sparking an even bigger conflict.

"Right now, the policy of the United States government is that we're not sending ATACMS," said Milley.

"We've had this conversation several times with my counterpart and others in the Ukrainian government."

Rather, he noted that the HIMARS and GMLRS have "proven to be very, very effective systems... against Russian forces".

"The range of the HIMARS is sufficient to meet the needs of the Ukrainians as they are currently fighting," he added.

US command spokesman Dave Butler also assessed that while Russia was firing its artillery at a higher rate than Ukraine, Kyiv's "are more effective".

Russia taking Ukrainian children

Zelensky has declined to name the settlements recaptured by Kyiv forces, but the US Institute for the Study of War, which follows in detail the fighting, said the Ukraine counterattack was near Balakliya and probably drove Russian forces back to the north side of the Siverskyi Donets and Serednya Balakliika rivers.

It appeared Ukraine forces also recaptured Verbivka and that Russian forces may have destroyed bridges to prevent Ukrainian fighters from pursuing them, ISW said.

"Russia's deployment of forces from Kharkiv and eastern Ukraine to Ukraine's south is likely enabling Ukrainian counterattacks of opportunity," it said.

In the territories occupied by Russian forces, the United Nations said there were "credible accusations" that Ukrainian children were being forcibly taken to Russia.

Some Ukrainians judged as close to the Ukraine government or military have also been tortured and forcibly removed and sent to Russian penal colonies and other detention centers, Ilze Brands Kehris, the assistant UN secretary general for human rights, told the Security Council.

But Russian UN Ambassador Vasily Nebenzya called the allegations unfounded and said what was labelled "filtration" was simply registering Ukrainians willingly fleeing the war to Russia.

© Agence France-Presse