Fighting in Syria (illustration)
Fighting in Syria (illustration) Reuters

The United Nations human rights chief said on Thursday that any side in Syria that has deliberately used starvation as a weapon has committed a "war crime."

UN High Commissioner for Human Rights Zeid Ra'ad Al Hussein, speaking in Qatar, said that those responsible should be prosecuted.

His comments came amid growing concern for citizens trapped in the Syrian town of Madaya, where 40,000 residents have endured a crippling siege by pro-government forces.

There has also been concern about people facing starvation in towns in the northwestern province of Idlib that are under siege from rebel forces.

"We condemn any such action," Zeid told journalists in Doha at the end of a two-day conference on human rights.

"Starving citizens is a war crime under international humanitarian law. Of course, any such action deserves to be condemned, whether it is Madaya or Idlib," he said.

"Should there be prosecutions? Of course, that should be the case. At the very least there should be accountability for these crimes."

Zeid, a Jordanian prince who has been the UN's most senior human rights official since September 2014, was speaking as it was reported that an aid convoy, the second of the week, had entered Madaya.

The UN has called for nearly 400 residents of the town who need immediate medical care to be evacuated.

More than two dozen people have reportedly starved to death there since December, sparking a global outcry.

Zeid said that Arab states needed to "open the door" to people fleeing conflicts such as the Syrian war.

"Yes, we could do more in the Arab world to open the door to take in more refugees," he said in response to a question.

Some Arab states, especially those in the Gulf, have come under intense international criticism for not allowing refugees from fellow Arab states into their countries.

The UN refugee agency estimates that more than four million Syrians have fled the war. Most have traveled to neighboring Lebanon, Jordan or Turkey.

AFP contributed to this report.