JERUSALEM: Israel warned more than one million residents of a northern zone around Gaza City to flee to the south as, according to a military spokesman, the Jewish state plans to step up air strikes to `increase pressure on Hamas`.

Israel believes that Hamas leaders and infrastructure are concentrated in the north.

But hundreds of thousands of civilians are said to remain in and around Gaza City.

`We have to enter the next phase of the war in the best conditions, not according to what anyone tells us,` spokesman Admiral Daniel Hagari told a press conference.

`From today, we are increasing the strikes and minimising the danger. We will increase the attacks and therefore I call on Gaza City residents to continue moving south for their safety,` Hagari added.

The Israeli military said it aimed to reduce the risks its troops would face as they enter Gaza in the `next phase of the war on Hamas` .

An Israeli siege has cut food, water, electricity and fuel supplies to the densely populated territory of 2.4 million people, sparking fears of a humanitarian catastrophe.

Tens of thousands of Israeli troops have deployed to the Gaza borderaheadofanexpected ground offensive that officials have pledged willbegin `soon`.

Israeli commanders visited frontline units on Saturday in a new sign of military readiness.

`We will enter Gaza, Israel`s chief of staff Gen Herzi Halevi told an infantry brigade on a visit.

`Gaza is densely populated, the enemy is preparing a lot of things there. But we are also preparing for them, Halevi said.

`We will enter for an operational mission, a professional one, to destroy Hamas activists,` he added.-AFP