In response to a call from Palestinian trade unions for May Day to be a day of action across the world in solidarity with Palestinian workers, protesters gathered early in London and marched to the Department of Business and Trade to blockade the building, in a symbolic ‘people’s embargo’ on arms sales to Israel.

Nearly a thousand took part, and with their bodies and massive banners they prevented access to the front doors of the building in Admiralty Place. Others blocked other entrances in Horse Guards Parade. There, police tried to physically move protesters who had linked their arms together, pushing and throwing people to the ground and arresting a few.

In the end, workers who had gathered around the building seem to have been told to go home, and campaigners called it a success.

The Department of Business and Trade is where arms export licences are processed and granted to companies like Elbit Systems and British Aerospace. These supply a lot of essential military equipment for drones and F-15 aircraft, used against civilians in Ghazzah.

Since 2015 at least £490 million worth of military exports have been granted by the UK government, but with 61 unlimited value open licences also given to arms companies, the true figure is likely to be much higher. It is difficult to uncover the true figure because the government hides behind Freedom of Information exemptions.

With the International Criminal Court poised to issue arrest warrants and investigating war crimes including genocide, many UK government workers are concerned that they may be complicit. On Wednesday at the blockade, outreach volunteers spoke with workers waiting outside the building and they say the reaction was generally positive, highlighting the issue effectively.