President Trump says 'it certainly looks' like Russia was behind spy attack

President Donald Trump said “it certainly looks” like Russia is responsible for the recent poisoning of a former Russian spy in the United Kingdom.

“It certainly looks like the Russians were behind it, something that should never ever happen and we’re taking it very seriously, as I think are many others,” Trump said in the Oval Office when asked by ABC News’ Jonathan Karl if Russian President Vladmir Putin was to blame.

Earlier in the day, the White House released a rare joint statement from the leaders of the U.S., France, Germany and the United Kingdom blaming Russia for the chemical attack on former Russian intelligence agent Sergey Skripal and his daughter in southern England last week.

"The United Kingdom thoroughly briefed its allies that it was highly likely that Russia was responsible for the attack,” the statement said. “We share the United Kingdom's assessment that there is no plausible alternative explanation, and note that Russia´s failure to address the legitimate request by the government of the United Kingdom further underlines Russia's responsibility."

The president’s assessment, which occurred shortly after his administration announced new sanctions against Russian entities for interference in the 2016 election, comes after the administration initially hedged on blaming Russia for the attack.

On Monday, British Prime Minister Theresa May accused Russia of perpetrating the attack and announced the expulsion of 23 Russian diplomats. The White House would not say if it shared in that assessment.

“We’ve been monitoring the situation very closely, take it very seriously,” White House Press Secretary Sarah Sanders said Monday. “We are standing with our U.K. ally. I think they're still working through, even, some of the details of that.”

Later that evening after speaking with British Foreign Secretary Boris Johnson, Secretary of State Rex Tillerson said the nerve agent “clearly came from Russia” but said it was unknown to him whether it was directed by the Russian government.

After President Trump spoke with Prime Minister May on Tuesday, the White House said the president agreed with her that Russia “must provide unambiguous answers regarding how this chemical weapon, developed in Russia, came to be used in the United Kingdom.”

On Wednesday, the UN Security Council held an emergency briefing on the chemical weapons attack. U.S. Ambassador to the U.N. Nikki Haley expressed solidarity with the United Kingdom and agreed with the assessment Russia was responsible.

“The United States believes that Russia is responsible for the attack on two people in the United Kingdom using a military-grade nerve agent,” she said. “If we don’t take immediate, concrete measures to address this now, Salisbury will not be the last place we see chemical weapons used. They could be used here in New York or in cities of any country that sits on this Council.”

The White House released a strong statement Wednesday saying the U.S. shares in the U.K.’s assessment.

"This latest action by Russia fits into a pattern of behavior in which Russia disregards the international rules-based order, undermines the sovereignty and security of countries worldwide, and attempts to subvert and discredit Western democratic institutions and processes,” Sanders said.

Russia has repeatedly denied responsibility for the attack and promised retaliatory measures against May’s decision to expel 23 Russian diplomats from the U.K.