Ukraine has been waiting for almost a month for the US defense secretary to sign off on critical missile supplies, Ukrainian President Volodymyr Zelensky said on Monday, as Russia stepped up attacks on energy and civilian infrastructure.

"In particular, we have been waiting for nearly a month for Mr Hegseth to sign off on missiles for Patriots and NASAMS. I instructed our team to raise this with the American side once again," Zelensky said on X/Twitter.

The Ukrainian leader has repeatedly called on the US, which supplies missiles purchased by NATO allies under a program known as PURL, to speed up deliveries ahead of winter.

Last week, US Secretary of State Marco Rubio acknowledged that a batch of interceptors may not have been delivered, but said that the delay was not for political reasons.

Delayed missile deliveries are adding to Ukraine's tensions with the US after US President Donald Trump announced a diesel deal with Russia and criticized Zelensky for Ukraine's unwillingness to stop attacks on Russian refineries.

Ukraine struggles with limited intelligence sharing, Starlink issues

In recent weeks, Ukraine said that at some point it experienced gaps in getting intelligence from the US on Russian missile attacks. It also reported that Starlink's military version has been throttled for days, disrupting military operations and air defenses.

Reuters has reported that the order to throttle Starshield came from inside the White House. Both SpaceX CEO Elon Musk and US officials have said publicly that any decisions on Starlink and Starshield limitations could only have been taken by the other.