1. ITV Report

Profile: Key challenges facing Mayor Boris Johnson

Boris Johnson during his acceptance speech Photo: PA

Now Boris Johnson has retained the keys to City Hall, what will the next four years hold for London and its triumphant Mayor?

With the eyes of the world on the capital this summer, the most immediate challenge facing the Mayor is ensuring a successful Olympics.

Boris Johnson will lead London through the 2012 Olympics Credit: PA

But there are many other items in Mr Johnson's in-tray and, despite his denials, there is also continued speculation about his ambitions beyond the mayoralty.The Olympics and Paralympics will provide the chance for London to shine on the global stage and the Mayor will be keen to make the most of the opportunity.But, as the man responsible for the Metropolitan Police, the security operation surrounding the event will be more important to Mr Johnson than British success in the medal table.And after the closing ceremonies have been staged, Mr Johnson has pledged to ensure a lasting legacy, creating 11,000 new homes from the athletes' village and 10,000 jobs.A successful Games will also help repair London's global reputation after last summer's riots.Mr Johnson also has ambitious plans for the capital's transport system, with the possibility of a "Boris island" airport to join the Boris bikes and buses.Dismissed as a vanity project by opponents, Mr Johnson remains committed to a new hub airport in the Thames Estuary as a way of easing pressure on Heathrow.

The possible estuary airport is a key part of Boris' vision Credit: PA

One transport project which will take off is the cable car across the Thames, which is scheduled to start taking passengers in the summer.

Mr Johnson has promised to cut waste from City Hall, reduce the mayoral share of council tax bills and create 200,000 jobs over the next four years.He has also committed to reduce Tube delays and increase the number of police on the beat.One of his campaign pledges was to negotiate a better deal for London with Prime Minister David Cameron.Questions about having designs on the top job himself have followed Mr Johnson but the former Henley MP has insisted he has no plans to return to the House of Commons to position himself as a possible Tory leadership contender.Last year he said: "I don't think I will do another big job in politics after this."