Downing Street insists Sir Keir will not step down.
Andy Burnham has started his by-election campaign saying he's running to "save" Labour.
If he wins Mr Burnham could mount a leadership challenge against Sir Keir Starmer
The Mayor of Manchester is to request permission to stand in an upcoming by-election
They say the health secretary will resign from the government tomorrow
Four ministers step down and more than 85 Labour MPs call on the Prime Minister to go
The prime minister pledges to oppose anyone who runs to replace him