A Ukrainian warplane has fired a weapon that hit a target inside Russia for the first time, a Ukrainian military source told Sky News.

The source said a "Russian command node" was hit on Sunday in the Belgorod area of ​​western Russia.

Belgorod is close to the border with northeastern Ukraine. It was not immediately clear what type of ammunition was used in the attack, including whether or not it was a Western weapon.

The United States and France recently said that Ukrainian armed forces were allowed to use their weapons to strike military targets inside Russia - from where Russian forces are launching attacks against Ukraine.

Under new guidelines approved by President Joe Biden, US munitions can be used on Russian soil to help defend the city of Kharkiv in northeastern Ukraine.

David Cameron, the British foreign secretary, has been less specific, saying it is up to Ukraine to decide how to use British weapons - such as Storm Shadow missiles from Ukrainian planes.

Speaking on condition of anonymity, the military source told Sky News: "A Ukrainian Air Force (UAF) mission has hit a Russian command node in Belgorod.

"While damage assessment is still taking place, it is confirmed as a direct hit. This is the first UAF air-delivered munition delivered against a target inside Russia."

Ukraine has launched multiple drone strikes deep into Russian territory. But using a fighter jet to strike targets inside Russia could be seen by Moscow as a new escalation.

The Russian defense ministry said its forces had shot down a number of Ukrainian drones in the Belgorod region. It was not clear if this was part of the same attack.

The Ukrainian military source also said that on Saturday evening, Ukrainian forces carried out a "coordinated attack" against a Russian landing craft that had recently moved into the Sea of ​​Azov from the Black Sea.

The ship has become the fifth of seven Ropucha landing craft that have been sunk or "made beyond repair" by Ukrainian attacks, the source said.

"This successful attack shows the Russians that they cannot operate freely either in the Black Sea or in the east," the source added.

The Russian military uses such ships to transport ammunition and supplies to the occupied city of Mariupol for transit forward to the front line, according to the source.

"By disrupting Russian shipments of munitions and key military supplies, this attack will directly support Ukrainian troops in their ongoing struggle," the source said.

Separately, Kiev's main military intelligence service said its forces had shot down an ultra-modern Russian fighter jet stationed at an air base nearly 400 miles from the front line, according to US media.

It was not immediately clear what weapons were used, but the airfield's distance from Ukraine suggests it was likely hit by drones, according to US media.

If confirmed, it would mark Ukraine's first known successful attack on a Su-57 fighter jet. This is a twin-engine stealth fighter jet described as Moscow's most advanced military aircraft.

Details of the latest Ukrainian strikes come as US media, citing a US senator and a Western official, reported on Wednesday that Ukraine had used US weapons to attack inside Russia in recent days.