Britain is "on track" to secure a lasting legacy from the 2012 Olympic and Paralympic Games in London, David Cameron said as he led events to mark the 200-day countdown to the opening ceremony.
Newly-agreed contracts for the long-term running of three more of the eight permanent venues would create 254 jobs for local people paid at London living wage rate, he announced.
And organisers remain confident of securing deals for the remaining two - the main stadium and the media centre - in time for the opening ceremony, they said.
The prime minister spoke as he prepared to gather senior colleagues at the Olympic Park in Stratford, east London, for a special Cabinet meeting focused on the major sporting event.
Ministers will afterwards fan out to visit sports facilities, businesses, schools and organisations across the UK in a co-ordinated push to promote the Games' value.
Cameron welcomed the confirmation of future ownership deals for the swimming and handball venues as well as the ArcelorMittal Orbit observation tower.
Details of the contracts are due to be set out today by the Olympic Park Legacy Company.
"As we kick off 2012, the year of the Olympic and Paralympic Games and the Diamond Jubilee, this is the perfect time for the Cabinet to come together and ensure we are doing absolutely everything we can to make the most of this unique opportunity to showcase all the great things the UK has to offer to the rest of the world," Cameron said.
"As ministers visit Olympic venues, businesses, schools and organisations associated with 2012 right across the UK, I want the message to go out loud and clear, from tourism to business, sport to investment, we are determined to maximise the benefits of 2012 for the whole country.
"Today, as we mark 200 days to go, and six out of the eight Olympic venues having already secured their future, we are well on track to delivering a lasting legacy for the whole of Britain."
The firms taking on the venues have committed to both recruit most staff from the local area and source goods and services from small and medium sized local businesses.
London mayor Boris Johnson said the contracts were "a ringing endorsement of our 2012 legacy and regeneration plans for east London and an amazing achievement by the Legacy Company.
"To find operators to take over these world class facilities so far ahead of the Games and to secure their commitment to spread jobs and opportunities throughout the local communities is the icing on the 2012 cake.
"We can now start the run into a fantastic year of celebration with huge pride and optimism that London will stage a great Games, delivering lasting sustainable benefits long after the athletes have departed."
Baroness Margaret Ford, chairwoman of the Olympic Park Legacy Company, said: "Our operators will play a key part in the creating a Queen Elizabeth Olympic Park that is a thriving visitor destination with world class sporting venues that are both affordable and accessible to the public.
"Their appointments are just another example of how London's legacy plans are further ahead than any previous host Olympic City.
"By working closely with sporting bodies and our local communities now, we can ensure that these venues will have a full and compelling programme of activities for when they reopen after the Games."