The British government is to spend £650,000 providing Syrian rebel fighters with hoods that protect against chemical weapons.
William Hague said the so-called escape hoods would be sent to "moderate forces" within the opposition, along with tablets that combat the symptoms of nerve agents and a type of paper that can detect chemical weapons.
The Foreign Secretary said the hoods protected against Sarin attacks for up to 20 minutes, meaning those wearing are able to move away from an affected area but cannot continue to fight. The tablets also provide those under a chemical weapons attack enough time to get to a medical centre to receive atropine, the drug needed to overcome Sarin.
In a written ministerial statement to MPs, Mr Hague said the assistance would be offered to the Supreme Military Council and the Syrian National Coalition.
The £656,800 cost of the non-lethal assistance would be met from the Government's conflict pool fund.
Mr Hague said the Government needed to "gift" the Syrian opposition fighters the equipment without going through the proper parliamentary procedures because it was "a matter of special urgency" as there was evidence Syrian President Bashar Assad was using chemical weapons in the conflict.
He said: "We have to be prepared to do more to save lives. There is evidence of attacks using chemical weapons in Syria - including Sarin.
"We believe that the use of chemical weapons is sanctioned and ordered by the Assad regime."
Mr Hague added: "We plan to equip the moderate armed opposition with 5,000 escape hoods, nerve-agent pre-treatment tablets (NAPs) and chemical weapons detector paper.
"Escape hoods protect against Sarin gas for approximately 20 minutes, allowing a person to move away from an affected area but not enabling them to continue to fight.
"They do not require fitting or extensive training to be effective. Pre-treatment with NAPs gives a person who is exposed to a nerve agent (including Sarin) a greater chance of reaching a place where atropine can be administered under medical supervision.
"Chemical weapons detector paper enables the basic detection of chemical weapons agents. The capability to detect quickly whether chemical weapons agents are present will inform decisions on whether or not to remain in an area and so potentially save lives."
Last week, MPs passed a Commons motion calling on the Government to seek the "explicit" consent of Parliament before deciding to arm rebel fighters in Syria.
The motion - that "this House believes no lethal support should be provided to anti-government forces in Syria without the explicit prior consent of Parliament" - was passed by 114 votes to one.
It had been tabled by Tory MP John Baron and was also supported by a number of high profile MPs, including Labour former minister Peter Hain and Tory former leadership candidate David Davis.
The vote came after Foreign Secretary William Hague told MPs they would be given a say on a substantive motion, which could in theory bind the Government to the decision, before rebels in Syria received military support from the UK.
But speaking after the G8 summit last month, Mr Cameron told the Commons there were certain circumstances where the Government reserved the right to intervene if it felt UK national interests were threatened.
Additional reporting Press Association