The world's most powerful atom smasher has been brought up to a record energy level, the European Organisation for Nuclear Research said Friday, in readiness for collisions that could generate new discoveries in particle physics.

"At just after 5.20 this morning, two 3.5 TeV proton beams successfully circulated in the Large Hadron Collider for the first time," said CERN in a statement.

"This is the highest energy yet achieved in a particle accelerator, and an important step on the way to the start of the LHC research programme," it said.

"The first attempt to collide beams at 7 TeV (3.5 TeV per beam) will follow on a date to be announced in the near future," it added.

The particle collider -- inside a 27-kilometre (16.8-mile) tunnel straddling the Franco-Swiss border near Geneva -- is aimed at understanding the origins of the universe by recreating the conditions that followed the Big Bang.

The collider was revived after a 14-month breakdown last November, following a technical glitch that put it out of action days after it was launched in September 2008.

"We have crossed an important milestone that showed that we can reach an energy of 3.5 TeV," CERN spokesman James Gillies told AFP.

"But there are still some tests to be done before the collisions," he said adding that these collisions would not happen for "around ten days."

Before the LHC experiment, no particle accelerator had exceeded 0.98 TeV. One TeV is the equivalent to the energy of motion achieved by a flying mosquito.