"It can carry all types of warheads," Major-General Shaukat Sultan told reporters on Saturday. It has a range of up to 1500 km, he added.
The test of the Ghauri (Hatf V) missile came just a few days after a new government took office in India. The new administration has pledged to continue a peace process with Pakistan, but postponed talks aimed at easing nuclear tensions, saying it needed time to settle in.
Pakistan says its weapons programme is a response to that of India, with which it has fought three wars since both countries won independence from Britain in 1947.
The Ghauri missile
A military statement said Prime Minister Zafar Allah Khan Jamali also watched the test-firing of the missile, but did not say where the test was done.
"The Ghauri missile ... is second only to Hatf VI Shaheen II in terms of range," it added. Pakistan test-fired the Shaheen II, with a range of 2000km, in March. It said it was capable of carrying nuclear warheads to every corner of India.
Khan was once revered as the
father of the atom bomb
The Ghauri missile was developed by Khan Research Laboratories, Pakistan's main uranium-enrichment facility, which was named for Abd Al-Qadir Khan, once revered as the father of the country's atom bomb.
Khan was sacked this year from his job as a special government adviser after he admitted exporting nuclear secrets to Iran, Libya and North Korea.
Some experts say the Ghauri missile was developed with North Korean help in return for nuclear know-how.