Boris Johnson has been accused of "hijacking" official local government resources for political campaigning, as the campaign for London Mayor hots up.
Johnson came under fire after today changing his official Mayoral Twitter account @MayorofLondon into @BorisJohnson, as he marked the start of official campaigning.
Johnson said the Twitter change was needed as election rules ban the use of City Hall resources for party political purposes.
However, critics have complained that he has taken more than 250,000 followers and they will now receive updates from Johnson as a party political candidate.
London Labour have said they will be making an official complaint and a spokesman for Ken Livingstone's mayoral campaign told the Huffington Post UK that Boris was "hijacking" the Mayoral Twitter account.
City Hall told the Huffington Post UK that it was a matter for the BackBoris campaign.
A spokesman from Johnson's re-election campaign told the HuffPost UK that complaints over Johnson's twitter usage "are not based on fact".
"The simple fact is that all Twitter accounts are owned by Twitter and this one was set up at zero cost to the taxpayer," he said.
"It is indeed telling that the critics who are seemingly so outraged now were notably silent when Ken Livingstone spent £3million a year of taxpayers' money on his Pravda - The Londoner.
"Boris has been completely transparent about changing the Twitter name and since it has changed we have seen a surge in followers despite followers being free to unfollow at any time. "
Sources close to the Information Commissioner told the Huffington Post UK that it was a "cause for concern".
They admitted that the implications over Twitter usage are "uncharted", adding that Johnson needs to do some "ironing out of what he can and cannot say in his professional capacity".
Johnson's use of Twitter has come in for criticism in the past. He was given an official warning after tweeting positively about the Sun's decision to back the Tories, from his Mayoral Twitter account: