The mayor of London was spared "deeply embarrassing" questions about the Silvertown Tunnel before the mayoral elections, a leaked email appears to show.

Officers within the Labour Party group at City Hall have been accused of rejecting four questions at mayor's question time (MQT) from an assembly member of the same party about the tunnel linking Silvertown and the Greenwich Peninsula.

These included asking if Sadiq Khan had rethought the modelling for the route as well as its possible impact on traffic in light of the Covid-19 pandemic.

Another rejected question asked why PM2.5 particles - a type of pollution which can harm human health - were not considered in an assessment of the tunnel's impact on air.

A leaked email sent on February 15, seen by this newspaper, states: "[Labour Group officers] are not prepared to submit these questions... they could prove to be deeply embarrassing for the mayor, especially so close to the mayoral elections."

%image(15041036, type="article-full", alt="Siân Berry, Green London Assembly Member")

Green party London Assembly member, Siân Berry, said: "It is absolutely shocking. That a group is saying to a member of the same group they can't ask the questions they want to completely goes against what the assembly stands for.

"We are there to ask the questions that need to be asked on behalf of Londoners."

%image(15258679, type="article-full", alt="Marchers say the tunnel will increase the amount of toxic air in Newham and Greenwich.")

A Labour Group spokesperson said: "Without seeing the email exchange, it’s hard to comment on the concerns raised.

"From time to time we have too many questions for MQT and we have to prioritise on the basis of what matters most to Londoners.

"This meant in recent months we’ve prioritised questions on tackling crime, the capital’s economic recovery, job creation and cleaning up our toxic air."

She added Labour assembly members are committed to delivering full and proper scrutiny – including on the Silvertown Tunnel, on which written questions were submitted for the last two MQT sessions.

City Hall's watchdog - its oversight committee - was looking into issues on Silvertown during the same period through correspondence with Transport for London (TfL), the spokesperson said.

Ms Berry was commenting at a march against the tunnel on Saturday, June 5.

Up to 300 people demanded Mayor Khan halt the controversial scheme, chanting "stop the tunnel, let us breathe" as they marched from Canning Town to The Crystal building.

%image(15258683, type="article-full", alt="Sadiq Khan has been urged to scrap the scheme.")

Co-organiser Simon Pirani - of campaign group Stop the Silvertown Tunnel Coalition - said: "What the people of Newham get out of this [tunnel] is more air pollution.

"[Sadiq Khan] has everything to gain from cancelling this project. It's a terrible idea."

Hundreds-join-march-to-protest-the-Silvertown-Tunnel

Mr Pirani claimed it is not too late for the mayor to halt the scheme, estimated to cost £2billion, which TfL says is designed to "reduce congestion and improve the reliability and resilience of the Blackwall Tunnel".

%image(15258687, type="article-full", alt="Marchers take their message to Britannia Village.")

Fellow organiser Victoria Rance described the turnout as "fantastic" as protesters strode through Britannia Village to the mouth of the tunnel.

Outside The Crystal - which is to become City Hall's new home - Newham Mayor Rokhsana Fiaz pledged to remain resolute in stopping the scheme.

"It makes no sense that in a global capital city - where too many Londoners are having their lives shortened [by air pollution] - this is allowed to happen," Ms Fiaz said.

%image(15258690, type="article-full", alt="Newham Green Party members on the march.")

Groups including Newham Green Party, Fossil Free Newham, the National Education Union, Newham Extinction Rebellion, Newham Stand Up to Racism and Mums for Lungs joined the protest.

%image(15258693, type="article-full", alt="Members of Choked Up cry: "What do we want? Clean air. When do we want it? Now!"")

Destiny Boka Batesa, 17, co-founder of campaign group Choked Up, said: "We must consider this as a race and class crisis.

"These communities are deprived and need our help. We must stand up for our rights to breathe good quality air."

%image(15258694, type="article-full", alt="Marchers stop the traffic in Silvertown Way.")

A TfL spokesperson said: "The Silvertown Tunnel will provide a public transport-focused river crossing.

"Once open, the tolled crossing will reduce congestion and improve the reliability and resilience of the Blackwall Tunnel, which will improve overall air quality in the area."

He added the majority of tunnel funding is raised through private finance which can’t be diverted to other projects.

Construction is underway, with piling for the launch chamber of the tunnel boring machine more than 75 per cent complete.

He added TfL will continue to monitor traffic and air quality during construction as well as when the tunnel is open to ensure overall traffic volumes and emissions do not increase.