William Hague told the House of Commons that the international community's policy on Syria has been an "abject failure".
The Foreign Secretary said £3 million had been allocated this month for the work with another £10 million to follow - urging other countries to do the same.
"The Cabinet is in no doubt that this is a necessary, proportionate and lawful response to a situation of extreme humanitarian suffering, and that there is no practicable alternative," he said.
Mr Hague was also keen to stress that more action may be required in the future, saying, "This is a situation where extreme humanitarian distress and growing international peace and security must weigh increasingly in the balance against other risks."
Adding that, "in our view if a political solution to the crisis in Syria is not found and the conflict continues, we and the rest of the European Union will have to be ready to move further and we should not rule out any option for saving lives."
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