Iran has launched a sub-orbital rocket for scientific research not a missile capable of reaching space as earlier reported, an aerospace official told an Iranian news agency on Sunday.

Ali Akbar Golrou, the executive deputy of Iran's aerospace research center, told Fars News Agency the rocket would not stay in orbit but could rise to about 150 km (94 miles) into atmosphere before falling to earth by parachute.

State television's Web site had earlier quoted the head of the aerospace research center, Mohsen Bahrami, as saying Iran had fired a missile able to reach space.

Iranian advances in building missiles capable of reaching space are watched closely by the West because the same technology could be used to build intercontinental ballistic missiles.

"What was announced by the head of the research center was the news of launching this sounding rocket," Golrou said, denying the earlier report.

So-called "sounding rockets" are often used to probe atmospheric conditions between 45 km and 160 km (28 miles and 100 miles) above the earth, between the maximum altitude of weather balloons and the minimum altitude of orbiting satellites.

Defense Minister Mostafa Mohammad Najjar had said on Saturday in comments published by the daily Etemad-e Melli that Iran was planning to build a satellite and launcher.

"Building a satellite and satellite launcher, as well as (previously) launching the first Iranian satellite called Sina with Russian cooperation, and becoming a member of the space club, are part of the Defense Ministry's plans," he said.

Iran launched its first satellite, Sina-1, into orbit from a Russian rocket in 2005 and has said it planned to modify its Shahab-3 missile, which Iran says has a range of about 2,000 km (1,250 miles), to launch satellites.