A free speech row has erupted after a man holding a provocative pro-Palestine sign was arrested outside Westminster Magistrates Court during a demonstration in support of Irish rap trio Kneecap.

The Metropolitan Police were on Wednesday accused of 'over-zealous policing' after a protester holding a sign containing the words 'Palestine' and 'action' was detained by officers.

It is the latest free speech challenge the police have faced following the proscription of campaign group Palestine Action.

Toby Young, co-founder of the Free Speech Union, remarked: 'This isn't quite as bad as the police arresting someone for holding up a sign saying "Plasticine Action", but it's excessive nonetheless.

'The over-zealous policing of pro-Palestinian protestors risks turning anti-terrorism legislation into a joke.'