Sacked US Secretary of State Rex Tillerson has warned of Russia’s “troubling behaviour and actions” in a parting statement after being fired by President Donald Trump.
He pointedly failed to thank Mr Trump or praise his policies.
The former ExxonMobil chief had a series of public rifts with the White House after being appointed last year.
Mr Trump officially fired Mr Tillerson via Twitter, naming CIA Director Mike Pompeo as his replacement.
Mr Trump also named Gina Haspel to become the CIA’s first female director.
How did Tillerson react?
Speaking to reporters at the Department of State, Mr Tillerson said good work had been done to have better relations with China, and rein in North Korea’s nuclear weapons programme.
But he added: “Much work remains to respond to the troubling behaviour and actions on the part of the Russian government.
“Russia must assess carefully as to how its actions are in the best interest of the Russian people and of the world more broadly.
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Continuing on their current trajectory is likely to lead to greater isolation on their part, a situation which is not in anyone’s interest.”
Sounding breathless and looking shaken, Mr Tillerson said he had spoken to the president to ensure clarity in the days ahead.
Although Mr Tillerson will not officially leave until 31 March, his deputy John Sullivan will take over running the state department pending the confirmation of Mr Pompeo.
“What is most important is to ensure an orderly and smooth transition during a time that the country continues to face significant policy and national security challenges,” Mr Tillerson said.
Trump’s reason for Tillerson sack
Speaking to reporters outside the White House on Tuesday, Mr Trump said his differences with Mr Tillerson came down to personal “chemistry”.
“We got along actually quite well, but we disagreed on things,” said the president.
“When you look at the Iran deal, I think it’s terrible. I guess he thought it was OK.
“With Mike, Mike Pompeo, we have a very similar thought process. I think it’s going to go very well.”
Mr Tillerson is the latest in a long list of senior officials who have either resigned or been fired since Mr Trump took office.
How was Tillerson fired?
The White House and Mr Tillerson have had a series of public disagreements – and that continued until the very end.
The two sides have offered different accounts of when the Secretary of State was told he was being fired.
The White House insists Mr Tillerson received a phone call on Friday from Chief of Staff John Kelly, who told him that he was being let go.
They say Mr Tillerson then asked if the announcement could be held until his return from a tour of Africa.
The top US diplomat’s team said he felt unwell on Saturday and decided to cut short his tour by a day.
His firing was reported by the Washington Post on Tuesday before any tweet was sent, according to a White House official.
But a statement released by Under Secretary Steve Goldstein implied that Mr Tillerson was first made aware of his firing by President Trump’s tweet.
“The secretary did not speak to the president and is unaware of the reason,” he said. After this statement was released Mr Goldstein himself was fired by the White House.
Mr Tillerson also said he received a call from the president about three hours after Mr Trump sent a tweet announcing his departure.