Calls are mounting for Sir Keir Starmer to grant Ukraine's request to fire Storm Shadow missiles into Russia.
Former Tory MP Bob Seely, who has been sanctioned by Russia for his criticism of Vladimir Putin, urged Labour to give the go-ahead.
Sir Keir rebuffed Ukrainian president Volodymyr Zelensky's request last week to fire Storm Shadow missiles deeper into Russian territory.
Mr Zelensky had urged the Prime Minister to 'show your leadership' by removing limits on how the long-range missiles can be used when he addressed the Cabinet on Friday.
It is understood that the UK and other allies allow Ukraine to fire long-range missiles defensively at targets on Russian soil near the border but not offensively or deep into Russian territory.
Calls are mounting for Sir Keir Starmer to grant Ukraine's request to fire Storm Shadow missiles into Russia. Pictured: Starmer and Zelensky shake hands during a meeting at 10 Downing Street on July 19
Russian President Vladimir Putin holds a meeting via videoconference on July 19
Former Tory MP Bob Seely (pictured), who has been sanctioned by Russia for his criticism of Vladimir Putin , urged Labour to give the go-ahead
Mr Seely, a former soldier, said yesterday: 'I don't quite know the difference between offensive and defensive targets.
'It's rubbish language – you either fire missiles inside a country or you don't,' he told the Mail.
'No one is talking about Ukraine invading Russia so this manipulation of language means nothing. Ukraine is hitting justified targets.'
Mr Seely also said that the Government should authorise use of the missiles against bases involved in Russian drone attacks.
He said: 'If there is a military location which is being used to wage war in Ukraine, that is a viable target.'
Meanwhile, former defence minister Tobias Ellwood said: 'Let's not tie Ukraine's hands with caveats placed on British, French and American long-range cruise missile systems that could be pivotal in crippling the Russian war effort in Ukraine.'
Mr Ellwood said it was important that the missiles are used responsibly on legitimate targets but added: 'For too long we've been spooked by Putin's threatening rhetoric.
Former defence minister Tobias Ellwood (pictured) said: 'Let's not tie Ukraine's hands with caveats placed on British, French and American long-range cruise missile systems that could be pivotal in crippling the Russian war effort in Ukraine'
Zelensky became the first foreign leader to attend a meeting of the British Cabinet in person since 1997 last Friday
'As with all dictators, he respects strength and exploits weakness. It's time to rekindle our Cold War state craft and stand firm behind Ukraine.'
It came after former prime minister Boris Johnson said in his Daily Mail column on Saturday: 'Over the past two years we have continually willed the Ukrainians the end – victory – without willing them the means.'
Mr Zelensky became the first foreign leader to attend a meeting of the British Cabinet in person since 1997 last Friday. The Ukrainian president urged the British Government to help with Kyiv's 'long-range capability'.
But following Cabinet and a one-on-one meeting between Sir Keir and Mr Zelensky, Downing Street said there was 'no change to our position' on weapons.
A No10 spokesman said: 'We have been providing military aid to support Ukraine's clear right to self-defence against Russia's illegal acts in accordance with international humanitarian law. Equipment provided by the UK is intended for the defence of Ukraine.'