David Cameron has vowed that Russia ‘must be made to pay’ as he confronted Moscow’s foreign minister over the invasion of Ukraine and the death of Russian opposition leader, Alexei Navalny.

The UK Foreign Secretary used a G20 meeting in Rio to challenge Sergey Lavrov over the Kremlin’s ongoing war and ‘murder’ of an opposition leader.

The meeting also saw the US, Australia, Canada, Germany, Italy, France and Norway call out Russia.

Mr Lavrov is said to have hit back at Western ‘fabrication’ over the death of Mr Navalny.

He was also mocked for setting out an ‘alternative set of facts’ about events in Ukraine.

Lord Cameron’s address to G20 foreign ministers came shortly after Britain slapped sanctions on the chiefs of the Arctic penal colony where Mr Navalny was killed.

‘Russia must be made to pay for its aggression,’ the Foreign Secretary told the summit.

‘There is no more serious issue for the world, and it’s the world that’s gathered here than one country invading another in this completely illegal and unacceptable way.

‘And the whole world should get behind Ukraine, should support Ukraine, and should call out the illegality of what Putin and his cronies have done.’

According to the BBC, Lord Cameron was joined by foreign ministers from France, Canada and Germany in naming Mr Navalny and blaming Russia for his ‘murder’ in front of Mr Lavrov.

The Kremlin politician was reported to have looked away and at his phone, before using his own speech to deny allegations of murder and calling them a ‘fabrication’.

Norway’s foreign minister Espen Barth Eide said Mr Lavrov replied to Lord Cameron’s remarks with ‘a set of alternative facts’ about events in Ukraine.

Mr Navalny, 47, is said to have fallen unconscious and died suddenly on Friday after a walk at the penal colony where he was serving a three-decade sentence.

Those in charge of his detention in the brutal prison camp were yesterday hit with asset freezes and travel bans by Britain.

The death of the vociferous Kremlin opponent occurred at the remote IK-3 prison – known as ‘Polar Wolf’ – in the Arctic Circle.

The Foreign Office pointed to the barbaric treatment of Mr Navalny, who spent his life exposing corruption by Mr Putin’s regime while being held as a political prisoner.