VLADIMIR Putin's envoys in the UK have refused to respond to Britain's ultimatum over the chemical attack on former Russian spy Sergei Skripal and his daughter Yulia in Salisbury. In a statement on Twitter the Russian embassy threaten retaliation if Theresa May was to respond with "punitive measures".

Theresa May earlier issued Russian President Vladimir Putin  24 hours to respond to claims that Russia was "highly likely" behind the attempted murder of Mr Skripal and his daughter Yulia.

The ultimatum has sparked World War 3 fears as Whitehall sources revealed the Prime Minister could launch a cyber attack on Russia in the wake of recent events.

It is thought Britain might target Kremlin propaganda machines, with Whitehall sources suggesting the UK will up the ante on its offensive cyber programme.

But the Russian embassy in the UK has hit back at the ultimatum and warned Mrs May against "punitive measures".

In a further blunt warning to the Prime Minister, Russia's foreign ministry spokeswoman Maria Zakharova added nobody should threaten a nuclear power, according to the nation's the state-run RIA news agency.

In a series of tweets the Russian embassy in the UK said: "Moscow will not respond to London's ultimatum until it receives samples of the chemical substance to which the UK investigators are referring.

"Britain must comply with the Chemical Weapons Convention which stipulates joint investigation into the incident, for which Moscow is ready.

"Without that, there can be no sense in any statements from London. The incident appears to be yet another crooked attempt by the UK authorities to discredit Russia.