Tesla CEO Elon Musk has been threatened by the head of Russia's space agency over his attempts to provide Ukraine with internet service.

Musk, 50, has been using Starlink - a constellation of more than 2,000 satellites in low Earth orbit - to beam internet connections to dishes around the world.

The service has a large presence in Ukraine, introduced with the explicit intention of keeping the country online amid the ongoing Russian invasion.

The billionaire said they had 'resisted hacking and jamming attempts' from the Russians back in April and were focusing SpaceX efforts on counter measures - at the expense of other projects.

Musk tweeted out information provided by Dmitry Rogozin, the head of the Russian space agency Roscosmos, to the Russian media on Sunday night. Rogozin posted the statement himself on Telegram.

Rogozin - who just yesterday boasted that Russia could destroy all NATO countries 'in half a hour' - accuses Musk of giving Starlink equipment to what they refer to as the 'Nazi Azov Battalion' as well as branches of the Ukrainian military.

'From the testimony of the captured chief of staff of the 36th Marine Brigade of the Armed Forces of Ukraine, Colonel Dmitry Kormyankov, it follows that the ground-based subscriber equipment of the Starlink satellite company Elon Musk was delivered to the militants of the Nazi Azov Battalion and the Marines of the Armed Forces of Ukraine to Mariupol by military helicopters,' Rogozin wrote.

'Elon Musk is thus involved with supplying the fascist forces in Ukraine with military communications,' Rogozin adds. 'And for this you will have to answer in an adult way, Elon, no matter how much you'll play the fool.'

As well as responding to attacks, officials say Starlink is giving Ukrainian forces the edge in winning the drone war as the nation fights back with technology to track down invading Russians.

The billionaire responded, as he often does, with his tongue pressed firmly in cheek.

'The word 'Nazi' doesn't mean what he seems to think it does,' Musk - who is in the process of attempting to purchase Twitter - tweeted.

He then added: 'If I die under mysterious circumstances, it's been nice knowin' ya.'

Many of Musk's fans responded to the missive, including his own mother, Maye Musk.

'That's not funny,' Musk's mother wrote with a few angry-faced emojis to go along with it.

'Sorry! I will do my best to stay alive,' Musk replied.

Rogozin has been feuding with the billionaire since the invasion began, calling him 'little devil' and criticizing the Tesla Cybertruck, according to Business Insider.

He even mocked Musk's attempt to buy Twitter, calling him 'moneybags' and mocking the idea that he would bring free speech to the platform.

SpaceX has launched more than 2,000 of its 'Starlink' space internet satellites into orbit and hopes to have 12,000 in the sky by 2026.

They form a constellation designed to provide low-cost broadband internet service from low Earth orbit.

While satellite internet has been around for a while, it has suffered from high latency and unreliable connections.

Starlink is different. SpaceX said its goal is to provide high-speed, cable-like internet all over the world....