UN secretary general Ban Ki-Moon has appealed for millions of dollars in aid to help the victims of Hurricane Haiyan, which killed thousands and left millions homeless when it struck the Philippines in November.

Touring areas south-east of Manila devastated by the storm to assess relief efforts, Ban addressed journalists amid the ruins and flattened housing of the city of Tacloban.

"I was very saddened by what I have seen in Tacloban - total destruction, and an enormous number of people have been lost, we need to support them," he said.

On the way to Tacloban, Ban's convoy drove through miles of devastation and refugee camps with rough shelters and tents housing thousands whose towns and villages were destroyed.

"Don't lose hope, don't lose hope," he told survivors.

This week, the UN launched an appeal for $800 million to provide food, shelter, medical supplies and housing to the 14 million people affected by Haiyan.

It said that about $237m, or 30% of the fund, had already been raised.

The hurricane, which is the strongest ever recorded to have struck land, hit the Philippines on November 8, killing 6,102, and leaving 4 million either homeless or with damaged homes. Approximately 1,800 people are still missing.

The UN has launched its largest ever aid appeal this year, asking for $12.9m from donors to help relief efforts for humanitarian disasters including the Syrian civil war.

"Of course, there are many other areas where we need the resources like supporting the Syrian refugees and Syrian people," Ban said. "But this time, this cannot be done alone. I appeal to the international community to support the Filipino people."

On Wednesday, the Philippines' President Benigno Aquino pledged that aid would not be siphoned off through corruption, as he appealed for support from the international community and unveiled the details of an $8.2 billion reconstruction programme for affected regions.