Dubai: Israel's Airport Authority announced Sunday it was closing the country's airspace to both inbound and outbound flights in the wake of the US attacks on Iranian nuclear sites.

The agency said it was shutting down air traffic “due to recent developments” and did not say for how long.

The US struck three sites in Iran early Sunday, inserting itself into Israel's war aimed at destroying the country's nuclear programme in a risky gambit to weaken a longtime foe despite fears of a wider regional conflict.

Meanwhile, Iran said there were “no signs of contamination” at its nuclear sites at Isfahan, Fordo or Natanz after US airstrikes targeted the facilities.

Iranian state media quoted the country's National Nuclear Safety System Centre, which published a statement saying its radiation detectors had recorded no radioactive release after the strikes.

“There is no danger to the residents living around the aforementioned sites,” the statement added.

Earlier Israeli airstrikes on nuclear sites similarly have caused no recorded release of radioactive material into the environment around the facilities, the International Atomic Energy Agency has said. (AP)