Keir Starmer's top legal adviser was under fire on Thursday evening after apparently comparing those who support leaving the likes of the European Convention on Human Rights to Nazis. Lord Hermer, the Attorney General, hit out at MPs and the media for being behind a 'siren song' pushing for Britain to drop international law. In a lecture at the Royal United Services Institute, a defence and security think-tank, he said the Labour Government had a 'policy of progressive realism' that means it will never leave international conventions such as the ECHR. Numerous senior politicians on the Right have called for Britain to leave the convention after it stopped Rwanda deportation flights. Lord Hermer said such 'songs' had been heard before, citing Nazi ideologist Carl Schmitt, who supported Hitler's policies such as the Night of the Long Knives assassinations. The Attorney General said: 'Our approach is a rejection of the siren song that can sadly now be heard in the Palace of Westminster and in some spectrums of the media, that Britain abandons the constraints of international law in favour of raw power. 'This is not a new song. The claim that international law is fine as far as it goes, but can be put aside when conditions change, is a claim that was made in the early 1930s by "realist" jurists in Germany, most notably Carl Schmitt, whose central thesis was in essence the claim that state power is all that counts, not law. 'Because of the experience of what followed in 1933, far-sighted individuals rebuilt and transformed the institutions of international law, as well as internal constitutional law.' He conceded that 'international law cannot stand still and rest on its laurels', that it must be 'critiqued and where necessary reformed and improved' and that 'we must be ready to reform where necessary'. But critics point out that the ECHR is unlikely to bow to calls for reform amid accusations it has overstepped its remit in a string of cases. Tory justice spokesman Robert Jenrick, an advocate of ending Britain's 72-year membership, said: 'The idea you can reform the ECHR is fanciful as it requires unanimity from all 46 signatories. 'It is appalling Hermer would insinuate those who think we should leave the ECHR are like the Nazis. '[Foreign Secretary] David Lammy tried that disgusting smeer with Brexiteers and it didn't work for him. It won't work for Hermer either. 'It seems Labour haven't learned a thing.' The row comes after complaints about Lord Hermer, who is a close friend of the Prime Minister, both having been human rights lawyers. His suitability has also been questioned after it emerged that, before taking up the role last year, he repeatedly brought cases against the Government on behalf of terrorists, including 9/11 plotter Mustafa al-Hawsawi and jihadi bride Shamima Begum. He also acted for former Sinn Fein leader Gerry Adams, who has always denied being a member of the IRA. The Attorney General's office was contacted for comment.