<P> In December 2001, it was announced that Meridian Delta Ltd. had been chosen by the government to develop the Dome as a sports and entertainment centre, and to develop housing, shops and offices on 150 acres (0.61 km) of surrounding land . It also hoped to relocate some of London's tertiary education establishments to the site . Meridian Delta is backed by the American billionaire Philip Anschutz, who has interests in oil, railways, and telecommunications, as well as a string of sports - related investments . </P> <P> A report in 2005 by the House of Commons Public Accounts Committee found that the cost of the process of selling the Dome and surrounding land (which increased to 170 acres from the initial offering of the 48 acres enclosed by the Dome) and managing the Dome until the deal was closed was £ 28.7 million . £ 33 million were expected to be returned to the taxpayer by 2009 . The value of the 48 acres occupied by the Dome was estimated at £ 48 million, which could have been realised by demolishing the structure, but it was considered preferable to preserve the Dome . </P> <P> The dome was publicly renamed as The O2 on 31 May 2005, in a £ 6 million - per - year deal with telecommunications company O2 plc, now a subsidiary of Telefónica Europe . This announcement, which presaged a major redevelopment of the site that retained little beyond the shell of the dome, gave publicity to the dome's transition into an entertainment district including an indoor arena, a music club, a cinema, an exhibition space and bars and restaurants . This redevelopment was undertaken by the dome's new owners, the Anschutz Entertainment Group, to a design by HOK SVE and Buro Happold . It cost £ 600 million, and the resulting venue opened to the public on 24 June 2007, with a concert by rock band Bon Jovi . </P> <P> During the 2012 Summer Olympics, the artistic gymnastics events, along with the medal rounds of basketball, were held at The O2 . It also held wheelchair basketball events during the 2012 Summer Paralympics . For sponsorship reasons, during those times the arena was temporarily renamed the North Greenwich Arena . </P>

When did the millennium dome became the o2 arena