Foreign Secretary William Hague was asked by the BBC at a security conference in the Gulf this morning whether he had seen proof that Syria was preparing such weapons.
We have seen some evidence of that. We and the US, as I said in parliament this week, have seen some evidence of that and that is why we have issued strong warnings about it. We have done so directly to the Syrian regime.
Pressed on what kind of evidence he had seen, Mr Hague replied:
We absolutely cannot be specific about that because clearly those are intelligence sources that these things come from. But we have seen enough evidence to know that they need a warning and they have received that warning.
Britain promised five million pounds to help opposition groups in Syria today - but stressed it would not be providing military aid.
Britain will expand its support to Syrian rebels with an extra £5 million of non-lethal practical assistance, the Foreign Secretary has said