DAVID Cameron has piled pressure on world leaders to deliver the "greatest possible pledge" of support to alleviate the suffering of Syrian refugees after he announced the UK was doubling its contribution with an additional £1.2 billion in humanitarian aid.

Opening an international conference in London, attended by 70 nations, the Prime Minster said it was time for a "new approach" to the crisis.

He urged other leaders at the talks to follow Britain’s lead, which has given £1.2bn over the last five years and will now give a similar amount over the next four.

At the same time, Mr Cameron called for assistance for Syria's neighbours - Turkey, Lebanon and Jordan - to enable them to open up job opportunities for the estimated 4.6 million refugees in their countries.

He also appealed for a commitment to ensure that all the refugee children in those countries had a school place by the end of 2016.

The Herald: Give more: David Cameron opens the Syria aid conference, urging fellow leaders to contribute more in aid

"If ever there was a moment to take a new approach to the humanitarian crisis in Syria surely it is now," declared the PM.

"We are facing a critical shortfall in life-saving aid that is fatally holding back our humanitarian efforts.

"After years of conflict we are witnessing a desperate movement of humanity as hundreds of thousands of Syrians fear they have no alternative than to put their lives in the hands of evil people-smugglers in search of a future."

Britain is co-hosting the conference with Germany, Norway, Kuwait and the United Nations. Countries represented include Iran, China and Russia.

No 10 stressed the aim of the conference was not only to raise as much money as possible but also to use that money to create opportunities for those refugees in the camps.

"It's about moving to a position where it is not just about funding the basics where people are kept alive in camps but also about giving them the opportunity to work and have a life for themselves while we work hand in glove with the international community to try and reach that peaceful, political settlement in Syria so eventually they can leave the camps and return home," explained a spokesman.

Pointing out the UK was the biggest donor behind the US, he added: "If you look at the range of countries and organisations at the conference today and the positive movements forward, there is a real sense of optimism that we can make in-roads in terms of raising the extra money that's needed and focus minds that we can deliver the right kind of aid..."

The UN is appealing for £5.4bn this year to fund aid operations for the 13.5m people displaced by the fighting and in need of assistance. It made a similar appeal last year but only reached half the target.

UN Secretary General Ban Ki-moon warned that financial support from the international community had failed to keep pace with the scale of the humanitarian crisis.

"Even if, by some miracle, the conflict ends tomorrow, the enormous humanitarian and development needs will continue for years and even decades," he explained.

Mr Ban said that only a political settlement could end the suffering of the Syrian people and expressed concern that peace talks in Geneva had stalled after two days after President Bashar Assad's forces launched a fresh offensive against rebels, backed by Russian air strikes.

"It is deeply disturbing that the initial steps of the talks have been undermined by the continuous lack of sufficient humanitarian access, and by a sudden increase of aerial bombing and military activities within in Syrian."

He added: "The situation is not sustainable. We cannot go on like this. There is no military solution. Only political dialogue will rescue the Syrian people from their intolerable suffering."

Today’s pledge will see the UK’s 2015’s pledge of £255m doubled to £510m for 2016, recognising the immediacy of the crisis.

Britain’s £1.12bn investment to date has included supplying:

*20m food rations;

*clean water to 1.6m people;

*2.5m medical consultations;

*4.6m relief packages and

*help with sanitation and hygiene for 7.2m people.

Videos courtesy of the Press Association