The British Prime Minister detailed "limited and targeted strikes" on chemical weapons facilities in Syria.
But May said intelligence pointed to the Syrian government being behind the suspected chemical attack on the rebel-held Damascus suburb of Douma last Saturday, and Defence Secretary Gavin Williamson said speed was "essential".
"We are prepared to sustain this response until the Syrian regime stops its use of prohibited chemical agents".
Konashenkov said that Russian Federation knew "for sure" that between April 3-6, the White Helmets - a group which helps civilians in opposition-held territory in Syria - were "under severe pressure specifically from London to produce as quickly as possible this pre-planned provocation". It is not about regime change.
Syria air strikes US President Donald Trump said the Syrian regime attacks"crimes of a monster
French President Emmanuel Macron said the strikes had been limited so far to Syria's chemical weapons facilities.
This is the first time as Prime Minister that I have had to take the decision to commit our armed forces in combat - and it is not a decision I have taken lightly.
"I have done so because I judge this action to be in Britain's national interest", she added.
In Douma, last Saturday a chemical weapons attack killed up to 75 people, including young children, in circumstances of pure horror. Western governments, including Britain, blamed the government of Bashar al-Assad, a Russian ally, for the attack.
"Very careful scientific analysis was applied to determine where best to target the Storm Shadows to maximise the destruction of the stockpiled chemicals and to minimise any risks of contamination to the surrounding area", the ministry said.More news: Swedish Academy head quits Nobel body amid sexual misconduct scandal
Correspondents from the British and world press also asked the prime minister to explain what role can the Parliament play in making a decision to attack another sovereign country.
"The Syrian regime has continued to use chemical weapons and will continue to do so".
She also said it had been "right and legal" to take action.
President Trump said the three allies had "marshaled their righteous power against barbarism and brutality".
This persistent pattern of behavior must be stopped - not just to protect innocent people in Syria from the horrific deaths and casualties caused by chemical weapons but also because we can not allow the erosion of the worldwide norm that prevents the use of these weapons.More news: New Zealand Wary Of Trump's Pacific Trade U-Turn
May is not obliged to win parliament's approval before ordering military action, but a non-binding constitutional convention to do so has been established since a 2003 vote on joining the USA -led invasion of Iraq.
Jeremy Corbyn, the leader of Britain's Labour Party, speaks at the launch of their local election campaign, in London, April 9, 2018.
Other opposition leaders joined in the criticism.
Vince Cable, leader of the Liberal Democrats, said: "Riding the coattails of an erratic U.S. president is no substitute for a mandate from the House of Commons".More news: Winnie Mandela Bore the Scars of Battle, Helped Heal a Nation