Pakistan successfully test-fired an intermediate range, nuclear-capable ballistic missile today, the military said.
Arch-rival India had been informed of the test beforehand, and was expected to conduct a missile test itself shortly.
"Pakistan can be justifiably proud of its defence capability and the reliability of its nuclear deterrence," Prime Minister Shaukat Aziz, who watched the test, was quoted as saying.
"Pakistan believes in peace that comes from a position of strength and operational readiness," he said.
The Hatf 5 missile, with a range of 800 miles, was first tested in 1998, the same year Pakistan and India conducted nuclear tests and became nuclear-armed states.
The neighbours embarked on a peace process in early 2004 after going to the brink of a fourth war in 2002.
Under an agreement on ballistic missile testing in late 2005, both countries notify each other in advance about tests, as one of several confidence boosting measures undertaken since peace talks began.
India and Pakistan expressed satisfaction with the way that accord was working at the end of two days of talks between their foreign secretaries in New Delhi earlier this week.