The United States is to donate another $100 million (76 million euros) in humanitarian aid to Syrian refugees boosting its total to $510 million, the State Department said Wednesday.
The additional funds, to be officially announced Thursday by Secretary of State John Kerry, will fund UN programmes for shelter, food and help to refugees in Jordan, Lebanon and Turkey as well as inside Syria, it said in a statement.
Washington has also given $250 million in non-lethal assistance to the Syrian rebels fighting to oust President Bashar al-Assad, and it is by far the largest single donor to the Syrian people caught in the bloody conflict.
According to UN figures, there are 1.2 million registered Syrian refugees who have fled the conflict pouring over the borders into neighbouring nations. As many as four million are also feared to have been displaced inside the country.
Washington voiced its "support and appreciation to those countries hosting refugees, and commends their efforts to provide protection and assistance to all who are fleeing the violence," the State Department said.
While it called on neighbouring nations to keep their borders open, it recognized "the significant strains on local populations and the economic impacts of providing aid to refugees."
The Zaatari refugee camp in Jordan, which shelters a large proportion of the 500,000 refugees inside the kingdom, is now the country's fourth largest city.
The $100 million in new funding would help the UN High Commissioner for Refugees, the UN children's fund UNICEF and the UN organisation for Palestinian refugees to provide shelter, schools, food and health care in the camps and elsewhere.
Nearly $43 million will go to Jordan to help provide some three million litres of water a day at the Zaatari camp, as well as building a new camp at Azraq and providing counselling and trauma services.
Some $32 million will be spent to help host communities who have taken in the Syrian refugees in Lebanon, which has also some 42,000 Palestinians, and "where living and social conditions are extremely challenging and needs overwhelm the available assistance," the statement said.
Turkey, which has some 17 camps dotted along the border with Syria, will benefit from some $9.5 million, while a further $16 million will be spent inside Syria.
The funds will help "internally displaced Syrians with basic necessities such as blankets, hygiene kits, clothing, and other items," while also aiding some 400,000 Palestinian refugees also hit by the violence.
Kerry was to officially announce the aid at the end of a four-day overseas trip to Moscow and Rome, aimed at trying to find a way to end the Syria conflict.