- Ukraine's allies have only sent it around half the heavy weapons promised, experts said.
- A tracking group said deliveries from the US, Germany, and the UK "remain well below promises."
Only around half of the heavy weapons that Ukraine's allies have promised to send it have actually been delivered, according to a new report compiled by the Kiel Institute for the World Economy.
The Kiel Institute, which has tracked aid promised and sent to Ukraine, said in an update on Thursday that while Western countries have made big military aid commitments to Ukraine "actual deliveries have been well below pledges."
"In general, only slightly more than half of the heavy weapons committed have been delivered. This is especially true for EU countries and the United States," it said.
Christoph Trebesch, the head of the team creating the tracker, said "the gap between promised and delivered military aid is wide."
The Institute also said that the size of the packages Ukraine's allies were committing to had fallen in the most recent period, from February 25 to May 31, which was when Ukraine was preparing to launch its counteroffensive efforts against Russian forces.
It said that the total amount of aid committed to Ukraine, which includes humanitarian and financial aid, as well as military help, was lower this spring compared to previous periods.
And while most of the new pledges were for military aid, those were "not as large as at the beginning of the year, and military equipment deliveries are well below commitments."
Ukraine has received weaponry like tanks, US-donated long-range HIMARS, which one expert told Insider were a "perfect" weapon for Ukraine, and UK-supplied Storm Shadow missiles that are proving highly accurate in taking out Russian targets. Ukrainian soldiers have also praised the robust US-donated Bradley IFVs.
The Kiel Institute said some European countries like the Czech Republic, Slovenia, Poland, and Slovakia had outperformed others, delivering "upwards of 80 percent of their promised heavy weapons."
That's compared to the US, Germany, and the UK, whose "deliveries remain well below promises."
Ukraine started its counteroffensive operations in June, and so far has made slow progress, though it claims that its main force has not yet entered the fight.
But Ukraine says it needs more weapons to be effective against Russia.
Valerii Zaluzhnyi, Ukraine's top general, said at the end of June that it "pisses" him off to hear commentators say the counteroffensive is moving slower than anticipated as it can't go any faster without more weapons.
"Without being fully supplied, these plans are not feasible at all," he said.
Ukraine's President Volodymyr Zelenskyy told CNN on Wednesday that earlier deliveries of Western weapons could have allowed its fightback to begin "much earlier."
He also said the delay gave Russia "the time and possibility to place more mines and prepare their defensive lines."
Experts told Insider's Chris Panella last month that NATO allies' hesitation in giving it more weapons is likely hindering Ukraine's counteroffensive efforts.