MPs have called for answers from the Government over a chemicals trade deal with Syria signed months after the bloodshed started.
The Department for Business issued licences for the export of sodium fluoride and potassium fluoride to the war-torn country in January last year before revoking them several months later.
The chemicals are capable of being used to make nerve gas such as sarin as well as having a variety of industrial uses, according to a scientist quoted by the Sunday Mail newspaper.
The Government said no chemicals were exported before the licence was revoked in June 2012 following EU sanctions but MPs said they intend to raise the issue at Westminster. The US says it believes chemical weapons were used in an attack by Syrian president Bashar Assad's regime on the outskirts of Damascus on August 21. It put the death toll at 1,429, including 426 children.
The SNP's Angus Robertson said: "This is utter hypocrisy from the UK Government - deploring chemical weapons in public whilst approving the sale of items needed to make them. I will be raising this at Westminster as soon as possible to find out what examination the UK Government made of where these chemicals were going, and what they were to be used for. Approving the sale of chemicals which can be converted into lethal weapons during a civil war is a very serious issue."
The member for Moray added: "We need to know who these chemicals were sold to, why they were sold, and whether the UK Government were aware that the chemicals could potentially be used for chemical weapons."
Dunfermline and West Fife Labour MP Thomas Docherty told the Sunday Mail he also plans to lodge questions at Parliament and will write to Business Secretary Vince Cable. He said: "At best it has been negligent and at worst reckless to export material that could have been used to create chemical weapons."
A government spokesman said: "The UK Government operates one of the most rigorous arms export control regimes in the world, and has been at the forefront of implementing an international sanctions regime on Syria. In January 2012, we issued licences for sodium fluoride and potassium fluoride. The exporter and recipient company demonstrated that the chemicals were for a legitimate civilian end use - which was for metal finishing of aluminium profiles used in making aluminium showers and aluminium window frames. Before any of the chemicals were exported, the licences were revoked following a revision to the sanctions regime which came into force on June 17 2012."
Chuka Umunna, Labour's shadow business secretary, said there were "very serious questions to answer as to why, in January 2012, export licences for chemicals to Syria which could be used in the manufacture of chemical weapons were approved". "It will be a relief that the chemicals concerned were never actually delivered," he said.
"But, in light of the fact the Assad regime had already been violently oppressing internal dissent for many months by the beginning of 2012 and the intelligence now indicates use of chemical weapons on multiple occasions, a full explanation is needed as to why the export of these chemicals was approved in the first place. This is important if confidence in the export licence process is to be maintained."