The Central Association of Agricultural Valuers (CAAV) has raised further question marks over government claims that only 500 farms per year will be impacted by a new proposed £1m threshold for Agricultural Property Relief (APR) from inheritance tax.

Addressing a Westminster committee in December, Keir Starmer, the British prime minister, repeated on two occasions that the government figures were certified by the Office of Budget Responsibility (OBR), a body which provides independent analysis of public finances. However, according to Jeremy Moody from the CAAV, the OBR only certified the data as “highly uncertain”.

“The OBR has not given the Government the confidence it claims for the figures it uses. The OBR report is not a defence; it is a certificate of uncertainty,” said Moody.

CAAV analysis suggests government is underestimating the number of affected farmers by a factor of five and that is before any account is taken of inflation over the coming years.