Labour has criticised Boris Johnson as a "part-time" mayor amid continued speculation that he will return as an MP before the end of his current term.
Renewed speculation in newspapers today suggested that Mr Johnson would announce his intention to stand for parliament at next year's general election by the summer.
A Labour source said the party would attack the mayor if he to "further his own political interests at the expense of the needs of Londoners".
Shadow justice secretary Sadiq Khan tweeted: "Wouldn't it be great if London's part-time mayor cared about our future as much as he cares about his own?"
Former mayor Ken Livingstone added: "Whether Boris Johnson is an MP, in the House of Lords or wherever it will make no difference as he doesn't do the day job as it stands, he leaves it to all his deputies."
Labour is calling for an overhaul of Stop and Search powers. It claims the impact the rules have on ethic minorities is shameful and that reform is urgently needed.
The arrest rate from searches has improved in London since 2009, but is still under 17%. Shadow Home Secretary Yvette Cooper also wants current guidance on avoiding race discrimination to be replaced with legislation.
An Labour MP, who once served as Minister for Sport, has been fined for jumping a red light in central London. Kate Hoey drove her Mini through a signal on Victoria Embankment last July. The light turned red just over a second before.
Kate Hoey, who has been MP for Vauxhall since 1989, was fined £240 after admitting going through the red light. She was also given three penalty points.
Londoners will be able to vote in American presidential-style primaries to choose Labour's next candidate for mayor.
Party members and people who register as Labour supporters can have their say.
The change announced today by Ed Miliband reduces the impact of trade unions on the selection of candidates.
The details now from our Political Correspondent Simon Harris
Labour's former deputy leader John Prescott has welcomed Ed Miliband's proposals to change the party's relationship with the trade unions.
Mr Prescott compared is proposals to the dramatic moves to introduce "one-member one-vote" (Omov) elections for the party leader under John Smith and end the Clause 4 commitment to nationalisation under Mr Blair.
Labour leader Ed Miliband announced he has appointed former Labour general secretary and union official Lord (Ray) Collins of Highbury to lead work on the introduction of a new system, which will consider an open primary process for the London mayoral candidate selection.
Lord Collins will also consider how the proposals could be spread to other parts of the country.
- Under Mr Miliband's proposals, any Londoner registering as a Labour supporter will be eligible to vote in the ballot to choose a candidate to replace Boris Johnson in 2016.
- A new code of conduct will be drawn up to cover all applicants to be Labour parliamentary candidates.
Ed Miliband has set out a series of reforms designed to reshape Labour's relationship with the trade unions and end the "machine politics" behind the alleged ballot-rigging controversy in Falkirk.
In changes which could provoke a major clash with the union bosses who bankroll his party, Mr Miliband said he would reform the system of affiliating union members to Labour.
He also said he would introduce a code of conduct for would-be election candidates and introduce open primary elections for Labour's next candidate for London Mayor.
US-style primaries prompt 'valuable debate' and make 'great strides in engaging the electorate, the shadow justice secretary said today, as Labour announced a new code of conduct over mayoral candidate selection after the Falkirk row.
Sadiq Khan wrote in the Evening Standard today: "Primaries help make politics exciting: for some time I’ve backed calls for such a process in London. So I support Ed Miliband’s landmark announcement today that Labour will use a primary to pick our candidate for London Mayor in 2016.
" All Londoners of voting age who are either a Labour Party member or have registered as a supporter will have a say in who becomes Labour’s candidate".