One of Jeremy Corbyn's inner circle, Chris Williamson, has announced he will step down from his frontbench role with immediate effect.
Williamson, who was shadow fire minister and is a close friend of Corbyn, quit just a day after he said council tax should be doubled on properties worth more than £320,000.
In his resignation statement, the Derby North MP said he would campaign "on a broader range of issues" and that he would "continue to loyally support the leadership of Jeremy Corbyn from the backbenches and hope to be a voice for the party's members".
Labour leader Corbyn praised the MP for his work, particularly relating to the Grenfell Tower disaster.
"I know that on the backbenches, Chris will be a strong campaigner on a range of crucial issues as well as serving his constituents with dedication," he added.
But his resignation is being linked with the council tax idea, which Labour is not thought to be currently considering.
It would affect a huge number of properties, particularly in London and the South East: As of October 2017, the last period for which data is available, the average house price in the UK was £223,807.
Williamson was criticised by the new housing minister Dominic Raab who said: "The last Labour government doubled council tax and now they want to hike it again. This latest plan would see people's bills soar by 20 per cent and add at least £320 a year to the average council tax bill."