Construction of the London 2012 Olympic Park will create jobs for a total of 30,000 workers, according to the organisers of the Games.
The Olympic Delivery Authority says 7,000 people have already worked on the east London site and of the current workforce, 23% are local residents.
The ODA also says it is creating 250 new apprenticeships on top of an existing 2,000 already planned.
Olympics Minister Tessa Jowell said Britain needed the 2012 Games.
"The investment of £6.1 billion in east London is precisely what east London needs, what London needs, what the country needs at this time because it is creating jobs," she told the BBC.
"One out of 10 of all the people working in the Olympic park are either an apprentice or they are people who are being trained, therefore leaving a legacy of skill."
Gordon Brown is due to visit the Olympic site in Stratford, and BBC political correspondent Reeta Chakrabati said the prime minister would make it clear the Games were part of his economic recovery.
"The cost tripled from the original bid from around £3bn to £9bn," she said. "There are many people who say this is something the country can ill-afford."
'Good progress'
The job announcement comes as work on the site reaches its halfway mark.
ODA Chairman John Armitt said the building work was "right on track".
The ODA said the current workforce of 3,315 would increase dramatically during 2009 as the pace of building work accelerates and would eventually reach a peak of 11,000 in 2010.
Overall, the total needed for all phases of development up to 2012 would be 30,000, it said.
Jobs created this year will include bricklayers, wood workers, electricians, security guards, engineers, plumbers, scaffolders and machine operators, as well as administrators and support staff.
At present, the ODA says nearly a quarter of employees are from east London and 57% are from the capital as a whole.
Almost one in 10 were previously unemployed, while the same number again are trainees or apprentices.
The ODA has committed to boosting further the number of people being trained on the Olympic site.
It says that to achieve this it will make it a condition that companies taking on new contracts provide at least the national average of apprenticeships - that is 3% of their workforce.
Mr Armitt said good progress was being made, with the Olympic Stadium taking shape and the first venue - the sailing facilities in Weymouth and Portland - completed.
"We are also delivering vital business, jobs and training opportunities in a tough time for companies and workers," he said. "Maximising apprenticeships on the Olympic Park is an important boost to this legacy."
The ODA also announced that a scheme to help unemployed people in the host boroughs has so far provided more than 300 with training and jobs.
And a programme specifically aimed at helping women get construction jobs has placed about 40 so far.
Lord Coe, chairman of the Games' organising committee, said: "At this halfway point, we are exactly where we want to be - and in some cases, ahead of schedule.
"This is a large and complex project and we don't have a day to waste, but I'm delighted with the progress the teams have made to date.
"We have lots of hard work ahead, but we will be ready, and we won't disappoint."
(Source: BBC Sport)
