The accusation, made by the American ambassador to the United Nations, Nikki R. Haley, came during a vitriolic exchange with her Russian counterpart at a meeting of the Security Council, which focused on a suspected chemical weapons assault in a Damascus suburb last week.
'It is about a limited and targeted strike that does not further escalate tensions in the region and that does everything possible to prevent civilian casualties.
Theresa May declined to say whether Syrian President Bashar al-Assad should stay in power and said talks with allies would continue on finding a political solution to the civil war.
In a statement published on his Facebook page Saturday, Corbyn said: "Bombs won't save lives or bring about peace".
The emergency Cabinet meeting came amid rising worldwide tension following the attack on the rebel-held town of Douma in Syria on Saturday which Western intelligence is convinced involved chemical weapons.
"This evening I have authorized British armed forces to conduct coordinated and targeted strikes to degrade the Syrian Regime's chemical weapons capability and deter their use".
Many MPs have called for Britain to act against Syria, warning that the use of chemical weapons was in breach of global law and could not be allowed to go unpunished. It was the basis for France's involvement in a joint military operation with the US and Britain to target Syrian chemical weapons facilities.
Syria has firmly denied any links to the attack.
Britain's defense ministry said "very careful scientific analysis" had been applied to maximize the destruction of stockpiled chemicals while minimizing any risk of contamination to surrounding areas.More news: Myanmar Minister Meets Muslim Rohingya Refugees in Bangladesh as Confidence-Building Measure
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"The facility which was struck is located some distance from any known concentrations of civilian habitation, reducing yet further any such risk", it added.
The mission was only allowed after approval by MPs - they backed military action in Iraq in September 2014, and in Syria a year later, strictly limiting strikes to IS targets. Britain has accused Russia of being behind last month's nerve agent attack on former Russian spy Sergei Skripal and his daughter in Salisbury, southern England, a charge Moscow has rejected.
Theresa May was given the go-ahead by the Cabinet yesterday to "take action" against the Assad regime.
"Following a discussion in which every member present made a contribution, Cabinet agreed it was vital that the use of chemical weapons did not go unchallenged".
British opposition lawmakers have called on May to give Parliament a vote before any military action. May isn't legally required to do that, though it is conventional for lawmakers to be given the chance to vote.
A YouGov poll for The Times newspaper this week indicated that only a fifth of voters believed that Britain should launch attacks on Syrian military targets and more than two-fifths opposed action.
Germany's chancellor says the allied strikes in Syria were - in her words - a "necessary and appropriate" response to what the USA and its allies say was a recent chemical attack in the Syrian city of Douma.
The condemnation by the United Kingdom and France followed earlier worldwide reaction to the attack in Douma.