ISLAMABAD, Pakistan — Pakistan on Tuesday test-fired the most advanced missile in its arsenal, capable of delivering a nuclear warhead deep inside rival India.

Although advance word to India averted a crisis, the launch of the Shaheen 2 is a vivid reminder of the stakes at play as South Asia's traditional enemies try to cement a fragile peace.

The missile has a range of 2,000 kilometres, meaning it could easily hit Bombay, New Delhi, Lucknow, Jaipur and other major Indian cities.

"Pakistan today successfully carried out the maiden test fire of the Shaheen 2 surface-to-surface ballistic missile," a military statement said.

Pakistan made certain to inform India in advance, and the test was not likely to damage relations that are rapidly improving. India's external affairs and defence ministries declined comment on the test.

The timing seemed more linked to internal Pakistani politics, with President Gen. Pervez Musharraf facing anger at home over an investigation into a black market run by rogue Pakistani scientists that allegedly sold nuclear know-how to Iran, Libya and North Korea.

Many Pakistanis feel the scientists have been made scapegoats and accuse Musharraf of jeopardizing the nation's nuclear program under pressure from the West.

The president, a key ally in the U.S.-led war on terror, announced plans to test-fire the Shaheen 2 at the same Feb. 5 news conference in which he pardoned Abdul Qadeer Khan, the father of Pakistan's nuclear program, who confessed to heading the nuclear proliferation ring.

Khan has been under virtual house arrest since the pardon, and at least six other scientists and administrators are in custody.

"This is internal politics," said Shahid ur-Rehman, the author of a widely read book about Pakistan's nuclear program. "It was basically aimed at quieting the Pakistani people who have been accusing Musharraf of rolling back the nuclear program."

The tests did cause unease abroad, however.

Japan said it "regrets Pakistan test-firing a ballistic missile amid the international community's efforts to prevent the proliferation of weapons of mass destruction and ballistic missiles," the Kyodo news agency reported.

There was no immediate reaction in Washington or in Israel. Jerusalem is about 3,550 kilometres from Islamabad, almost twice as far as the range of the missile.

Pakistan's previous longest-range missile was the Ghouri, first tested in 1997, which has a range of 1,300 kilometres. Experts say the Ghouri design is remarkably similar to the North Korean No Dong missile. Pakistan has acknowledged getting missile technology from North Korea, but has denied it bartered its nuclear expertise.

The Shaheen 2 is believed to have been designed by Pakistani scientists based on Chinese technology that is distinct from the No Dong, ur-Rehman said.

The armed forces on Tuesday took pains to play up the role of Pakistani scientists in the successful test of the Shaheen 2.

"The test demonstrates Pakistan's advanced scientific capability in the strategic field and is a tribute to the brilliance, hard work and patriotism of its dedicated community of scientists, engineers and technicians," the statement said.

"By the Grace of Allah, all the planned technical parameters were successfully validated during the test fire," it said.

India and Pakistan routinely conduct missile tests as part of their defence strategy but have also used them to send political messages or ratchet up tension.

Pakistan conducted a nuclear test in 1998, following a similar test by India, bringing years of crippling sanctions from the West.

The two nations nearly went to war in 2002, but relations have been on the upswing lately. Last month, India and Pakistan set themselves a roadmap to peace that will include negotiations to solve their dispute over divided Kashmir -- the issue at the heart of five decades of hostility.

On Tuesday, an Indian delegation was in Islamabad to discuss resumption of a bus route from the western Indian state of Rajasthan to Pakistan's southern Sindh province, suspended since 1965.

Foreign Ministry spokesman Masood Khan said Pakistan's strategic goal was to have a "minimum credible deterrence."

"We have to test these missiles from time to time," he told a news conference. "When we do take the test, we inform neighbours and concerned countries."

That sentiment seemed to be well received in India.

"We should not see every missile test as a threat," said C. Uday Bhaskar, an analyst at India's Institute of Defence Studies and Analyses, a government-funded think-tank in New Delhi.

"Both India and Pakistan inform each other about these tests in advance. We should see this as a normal activity."