A security expert in Israel talks of Pakistani hands helping Iran with its missile advances after a modified version of an Iranian ballistic missile was tested by Tehran.

Iran successfully test-fired a new deterrent medium-range surface-to-surface missile, dubbed Sejjil-2, on Wednesday.

The plus-2000-km-range surface-to-surface missile works with solid-fuel and therefore has greater deterrence power as it lowers the time needed to prepare for launch.

Sejjil-2's range is comparable to the liquid-fueled Shahab III.

However, a solid-fuel rocket is believed to have the potential to be stored in mountains, moved around and reassembled — making it more difficult to intercept — , and fired on shorter notice.

Following the launch of Sejjil-2, Yiftah Shapir of the Institute for National Security Studies at Tel Aviv University said the latest Iranian missile technology — unlike the Shehab-3 — is not based on Soviet and North Korean Scud technology.

"It is closer to a Pakistani missile, the Shaheen II," Shapir told Haaretz.

The report by the Israeli daily Haaretz suggested that the nuclear-armed Pakistan may be involved in supplying Iran with technology for the development of the Sejil-2.

The report by Haaretz comes in line with Western claims, accusing Iran of having had close links for at least 20 years with both North Korea and Pakistan.

The western media also claim that Abdul Qadeer Khan, the father of Pakistan's nuclear program, brokered many deals with Iran on the matter and acted as a middleman to funnel "crucial technology" to Tehran.

Although Khan had admitted in 2004 to passing nuclear information to foreigners - including Iran, North Korea and Libya, he said in a May interview with the Guardian that he had been forced to make the confessions.

"It was not of my own free will. It was handed into my hand," Khan said in a May 2008 interview, adding that former Pakistani President Pervez Musharraf had forced him to make the confession.

Iran says its nuclear and missile projects have originated from domestically-developed technology, adding that it has never had dealings with Khan.

The UN Security Council has approved three sets of economic sanctions against Iran to try to force it to abandon its nuclear and missile programs.

After the launch of Sejjil-2 on Wednesday ruffled feathers in Western circles, Iranian President Mahmoud Ahmadinejad said, "They thought we would retreat but that will not happen. I told them you can adopt 100 sets of sanctions, but nothing will change."