SYDNEY - Australia Thursday tightened its sanctions on Iran in a fresh bid to convince Tehran to allay international concerns over its nuclear drive.

Foreign Minister Stephen Smith said the new measures target more than 100 Iranian groups and companies, and restrict Australian business dealings with the country`s oil and gas sector.

"In adopting this package, Australia stands at the forefront of international community efforts to have Iran meet its international obligations in relation to its nuclear program, one of the most serious security challenges facing the international community," he said.

The measures also include a ban on trading weapons and items which could be used for nuclear, chemical or biological arms or missiles.

They follow this month`s new United Nations Security Council resolution against Iran and fresh sanctions announced by the European Union and Canada.

BDST: 1153 HRS, July 29, 2010