The plans for a Holocaust memorial next to Parliament are "not good enough for the memory of the victims of the Nazi slaughter, including my grandparents", Baroness Deech has said.

The crossbench peer, whose father Josef Fraenkel fled to England to escape the Nazis, wrote that the "bitterly contested" plans had been "politicised", claiming: "To suggest that opposition to this scheme is antisemitic is shocking."

Baroness Deech is a longstanding critic of the plans to build the memorial and learning centre in Victoria Tower Gardens.

The plans, which Westminster Council is currently considering, have received wide support from across the political spectrum but staunch opposition from enviromental and heritage groups over its impact on the park.

"This bitterly contested plan does not speak to the heart. It is not good enough for the memory of the victims of the Nazi slaughter, including my grandparents," Baroness Deech wrote in House magazine.

"Some have likened it to a giant toast rack, lacking in obvious historical reference to the deaths of six million Jews. Where the symbolism of a memorial is not immediately apparent to the passer-by, it tends to be treated with disrespect, as I have seen at the Berlin open-air memorial. 

"Most inappropriately, the planning application to Westminster city council has been politicised. To suggest that opposition to this scheme is antisemitic is shocking. It is as if this project is being used by the government to distance itself from allegations surrounding Jeremy Corbyn; while the Labour party may be unwilling to object for the same reasons.

"But many Jews are unhappy about it, and feel it is being steam-rollered through the community."

She noted organisations such as Royal Parks, Unesco, the Environment Agency, the Victorian Society and Historic England have all voiced opposition to the scheme.

"The drawbacks [to the location] are many: the loss of a park, in an area where there is little green space and a playground," she added.

Despite the opposition, the scheme has been called a "national, sacred mission" by Theresa May and all the living former prime ministers - David Cameron, Gordon Brown, Tony Blair and Sir John Major - have spoken in its support.

"In the face of despicable Holocaust denial, this memorial will stand to preserve the truth forever," Mrs May said.