Israel will deploy its "Iron Dome" multi-million-dollar missile defence system in southern Israel for the first time next week in the wake of rocket attacks from Gaza, officials said Friday.

"I authorised the army to deploy in the next few days the first battery of "Iron Dome" for an operational trial," Defence Minister Ehud Barak said as he toured the tense Gaza Strip border.

The order comes after a spate of rocket fire by Gaza militants in recent days, some of them striking deep into Israel.

The deployment of the Iron Dome interceptor, designed to combat short-range rocket threats from the Gaza Strip and Lebanon, has been delayed until now with officials saying operating crews needed more training and suggestions the system was prohibitively expensive.

The system, developed by Israel's Rafael Advanced Defence Systems with the help of US funding, is designed to intercept rockets and artillery shells fired from a range of between four and 70 kilometres (three and 45 miles).

Each battery comprises detection and tracking radar, state-of-the-art fire control software and three launchers, each with 20 interceptor missiles, military sources said.

However, Barak said the deployment would be experimental and partial and complete protection could take years.

"The complete acquisition of Iron Dome will take a number of years, dependant on suitable funding," he said.

Militants in Gaza and those allied with Lebanon's Hezbollah militia have fired thousands of projectiles at Israel in the past.

The system will first be along the border of the Hamas-run Gaza Strip, from where militants fired a daily barrage of home-made rockets prompting Israel to launch a devastating 22-day offensive in December 2008.

It will then be deployed along the Lebanese border, from where Hezbollah militants fired some 4,000 rockets into northern Israel during a 2006 war. It was that experience which prompted the development of Iron Dome.

Israel believes Hezbollah now has an arsenal of some 40,000 rockets.

In May, US President Barack Obama asked Congress to give Israel 205 million dollars to develop the system, on top of the annual three billion dollars Israel receives from Washington.

Iron Dome will join the Arrow long-range ballistic missile defence system in an ambitious multi-layered programme to protect Israeli cities from rockets and missiles fired from Lebanon, the Gaza Strip, Syria and Iran.

A third system, known as David's Sling, it currently being developed with the aim of countering medium-range missiles.