Water tanks and other sanitation equipment capable of helping an estimated 150,000 refugees from war-torn Syria were shipped out from Bicester on Thursday last week.
The 25 tonnes of equipment, funded by UNICEF, will be used by Oxfam and UNICEF to help refugees fleeing the violence in Syria.
On Saturday, the equipment was flown from Heathrow Airport to Amman in Jordan, where it will be sent to a number of refugee camps.
Oxfam spokesman Jane Cocking said: “The conflict is having a devastating impact on the people of Syria. Thousands of people have fled their homes, leaving everything behind.
“Many have been living in tents and overcrowded accommodation for months already. The rising temperatures will make the situation even worse.
“Clean water and safe sanitation are vital to curb the spread of disease.”
More than 93,000 Syrians have already lost their lives in the conflict, and an estimated 1.5 million people have fled the conflict into neighbouring countries, over half a million of which are in Jordan.
More than half the refugees are children, who are at particular risk from poor sanitation.