Chelsea have been warned that their stadium is 'too small' by Sadiq Khan and that they must be watching their London rivals with 'envy'.
But the Mayor of London has invited the Premier League giants for talks over potentially opening a new stadium.
Chelsea's owners are seemingly divided over whether to redevelop Stamford Bridge or build on a new site at Earl's Court, which would require consultation with the mayor's office.
The Blues have the 10th-biggest capacity in English club football at 40,343, lower than Championship side Sunderland.