"When international monitors are arriving in Damascus, and – more broadly – when the Syrian government and large parts of the opposition are moving towards creating a constitutional committee to end the war, to say that 'there is no practicable alternative to the use of force if lives are to be saved' is hypocritical, to say the least," the embassy said in a statement.
The embassy also said that the concept of "humanitarian intervention" used by the UK does not serve as a legal basis to support airstrikes on Syria without a UN mandate.
The embassy underscored that the West's missile strike on Syria constitutes an attack under a false pretext, supported by a false legal basis, and has delivered a false result.
"Let’s leave legal details to lawyers. But one doesn’t need deep expertise to see that we are dealing with an attack under a false pretext, a false legal basis and a false result," the embassy said.
The statement comes as UK Prime Minister Theresa May claimed that Russia's UN Security Council veto is an attempt to block the OPCW investigation in the Syrian town of Douma, where the purported attack is said to have occurred. In the meantime, the strikes themselves are being considered an attempt to undermine the OPCW work in the town.
"There were clearly attempts to block any proper investigation, as we saw with the Russian veto at the UN earlier in the week. And we cannot wait to alleviate further humanitarian suffering caused by chemical weapons attacks," May said.
May said that the UK joined the attack on Syria out of "national interest."
"Let me be absolutely clear: we have acted because it is in our national interest to do so. It is in our national interest to prevent the further use of chemical weapons in Syria — and to uphold and defend the global consensus that these weapons should not be used. For we cannot allow the use of chemical weapons to become normalized — either within Syria, on the streets of the UK or elsewhere," May said.
"We have done it because we believed it was the right thing to do. And we are not alone. There is broad based international support for the action we have taken. Over the weekend I have spoken to a range of world leaders — including Chancellor Merkel, Prime Minister Gentiloni, Prime Minister Trudeau, Prime Minister Turnbull and European Council President Donald Tusk. All have expressed their support for the actions that Britain, France and America have taken," the prime minister declared.