By Jeremy Diamond and Allie Malloy, CNN

(CNN) -- The United States, European Union countries, Canada and Ukraine expelled more than 100 Russian diplomats on Monday in response to Russia's alleged use of a nerve agent to poison a former Russian spy living in the United Kingdom.

President Donald Trump on Monday ordered the expulsion of 60 Russian diplomats the US identified as intelligence agents and the closure of the Russian consulate in Seattle, the most forceful action Trump has taken against Russia to date. Of those being expelled, 48 of the alleged intelligence agents work at the Russian embassy in Washington and 12 are posted at the United Nations in New York, senior administration officials said.

British Prime Minister Theresa May called the collective move "the largest expulsion of Russian intelligence officers in history."

"We have no disagreement with the Russian people who have achieved so much through their country's great history. But President Putin's regime is carrying out acts of aggression against our shared values," she said Monday. "The United Kingdom will stand shoulder to shoulder with the EU and NATO to face down these threats."

Trump took the action after the US joined the United Kingdom in accusing Russia of attempting earlier this month to murder a former Russian double agent and his daughter using a nerve agent in the town of Salisbury, England. The action comes just 11 days after the Trump administration leveled the first sanctions against Russia for its interference in the 2016 US presidential election.

"The United States takes this action in conjunction with our NATO allies and partners around the world in response to Russia's use of a military-grade chemical weapon on the soil of the United Kingdom, the latest in its ongoing pattern of destabilizing activities around the world," White House press secretary Sarah Sanders said in a statement.

"Today's actions make the United States safer by reducing Russia's ability to spy on Americans and to conduct covert operations that threaten America's national security. With these steps, the United States and our allies and partners make clear to Russia that its actions have consequences," she said. "The United States stands ready to cooperate to build a better relationship with Russia, but this can only happen with a change in the Russian government's behavior."

Sanders also added that the closure of the Russian consulate in Seattle was tied to the consulate's "proximity to one of our submarine bases and Boeing." A senior administration official declined to say whether the US believes Russian agents were spying on US submarine bases.

The consulate closure and the expulsion of dozens of diplomats came on the heels of the UK's expulsion of 23 Russian diplomats. Fourteen European Union member states, Canada and Ukraine also moved on Monday to expel Russian diplomats.

Ukraine expelled 13 Russian diplomats over the incident. Canada, Germany, France and Poland each expelled four Russian diplomats. Italy, Estonia, the Netherlands, the Czech Republic, Lithuania, Romania and Finland also expelled between one and three diplomats each.

"Additional measures, including further expulsions ... are not to be excluded in the coming days and weeks," European Council President Donald Tusk said Monday, speaking in Bulgaria.

He said the European Council agreed with the UK "that it is highly likely the Russian Federation is responsible" for the poisoning.

"We remain critical of the actions of the Russian government," Tusk added.

Senior Trump administration officials said the actions were being taken not only as a direct response to that attack, but also to rebuke Russia's "steady drumbeat of destabilizing actions."

The actions came less than a week after Trump spoke with Russian President Vladimir Putin to congratulate him on his reelection. Trump did not raise the nerve agent attack during the call, and senior administration officials said the two leaders have not spoken since.

But a senior administration official said the United States' retaliatory action was "absolutely" Trump's decision, saying it was "something he was involved in from the beginning and that he personally made after several meetings with his team last week."

The expulsion still leaves dozens of Russian intelligence officers working under diplomatic cover in the US. A senior administration official said the US estimates more than 100 Russian intelligence officers are currently in the US.

Russia said earlier on Monday it planned to retaliate against the US if its diplomats were expelled, with a Kremlin spokesman saying "the principle of reciprocity will be enforced" before the US announced its plans to expel Russians.

The move comes about 15 months after the Obama administration expelled 35 Russian diplomats in response to Russian meddling in the 2016 US presidential election.