India will next month test a new long-range nuclear-capable missile which can strike targets more than 5,000 kilometres (3,100 miles) away, a defence research spokesman said on Wednesday.

The announcement came three months after India successfully tested its Agni-IV missile, which was previously the longest range missile possessed by the armed forces capable of travelling 3,500 kilometres.

"The trial of Agni-V is planned for March and its individual technologies and sub-systems have been tested and everything is fine," a spokesman for the Defence Research and Development Organisation (DRDO) told AFP.

"Agni-V is a highly accurate and state-of-art missile system which can carry nuclear weapons," the official said, declining to disclose the size of the warhead it could carry.

Agni means fire in Sanskrit language.

The DRDO spokesman said India, which carried out a string of nuclear detonations in 1998, was developing an array of ballistic missiles as a "deterrence" and the move should not be seen as a threat to any country.

"Our strategic missiles are for deterrence and are not country-specific. They are meant to ensure peace," the spokesman said.

The Agni series is being developed by the DRDO under an Integrated Guided Missile Development Programme launched in 1983.

India is among the world's top 10 military spenders. It plans to splurge $50 billion by 2015 to upgrade its million-plus military.

India, which will soon clinch a deal for 126 warplanes that can carry nuclear-tipped bombs, has fought three wars with historical rival Pakistan since their independence in 1947.

It also fought a brief but bloody conflict with uneasy neighbour China in 1962 over their border dispute, which remains unresolved despite several rounds of high-level negotiations.