Trump said he has ordered "precision strikes" against Syria, where dozens of people were killed last weekend in a suspected toxic gas attack on Douma, the largest town in a former rebel stronghold outside Damascus.
She will repeat Saturday's assertion that Britain was "confident in our own assessment that the Syrian regime was highly likely responsible" and that it could not wait "to alleviate further humanitarian suffering caused by chemical weapons attacks", according to excerpts of her speech.
Britain's defense ministry said initial indications were that the precision weapons and meticulous target planning had "resulted in a successful attack". "We are prepared to sustain this response until the Syrian regime stops its use of prohibited chemical agents", he said.
But she will be grilled over why she broke with a convention to seek parliamentary approval for the action, a decision that she and her ministers say was driven by the need to act quickly.
Trudeau in 'financial' talks to resolve heated pipeline dispute
Horgan emerged from the meeting Sunday showing no intention of letting off on his opposition to the pipeline. He said whatever financial arrangement is reached will include protections for taxpayers.
"This collective action sends a clear message that the worldwide community will not stand by and tolerate the use of chemical weapons", May told a press conference. Russian Federation and Syria claim the attack was fabricated.
"I have done so because I judge this action to be in Britain's national interest", she added.
Syrians flooded the streets to celebrate the triumph of the country's army against a US-UK-French coalition strike, teleSUR correspondent Hisham Wannous reported..
Many politicians in Britain, including some in May's own Conservative Party, had called for parliament to be recalled from a break to give authority to any military strike.
US, allies hit Syria as Russian Federation fumes
Sergey Rudskoy said that Russia might consider sale of the S-300 systems to Damascus following US-led strikes against Syria. Earlier in the day, Chief of the Main Operational Directorate of the Russian General Staff Col.
Opposition Labour leader Jeremy Corbyn had said Britain should press for an independent United Nations -led investigation into the suspected chemical attack in Douma rather than wait for instructions from Trump on how to proceed.
The DUP has backed Prime Minister Theresa May's decision to authorise air strikes in Syria.
He also did not rule out future military action.
She said that at an emergency cabinet meeting in London on Thursday "we agreed that it was both right and legal to take military action" after hearing legal advice.
US preparing new sanctions on Russia over Syria, Haley says
Russian president Vladimir Putin warned on Sunday that further western attacks on Syria would bring chaos to world affairs. Mr Nebenzia accused the US, UK and France of "hooliganism" and of "demonstrating a blatant disregard for global law".
Shortly after the military strikes were launched, Scotland's first minister Nicola Sturgeon said United Kingdom foreign policy should be set by Parliament and not Donald Trump after the U.S., United Kingdom and France bombed targets in Syria.