US President Donald Trump appears to have changed his story about a 2016 meeting at Trump Tower that is pivotal to the special counsel's investigation, tweeting that his son met with a Kremlin-connected lawyer to collect information about his political opponent.
"Fake News reporting, a complete fabrication, that I am concerned about the meeting my wonderful son, Donald, had in Trump Tower," Trump wrote in a Sunday tweet.
"This was a meeting to get information on an opponent, totally legal and done all the time in politics - and it went nowhere. I did not know about it!"
But 13 months ago Trump, gave a far different explanation for the meeting.
A July 2017 statement dictated by the president but released under the name of Donald Trump Jr., read: "We primarily discussed a program about the adoption of Russian children that was active and popular with American families years ago."
The latest twist came amid a series of searing tweets sent from his New Jersey golf club, in which he tore into two of his favourite targets, the news media and Robert Mueller's ongoing investigation into possible links between the president's campaign and Russia.
Trump unleashed particular fury at reports that he was anxious about the Trump Tower meeting attended by Donald Trump Jr. and other senior campaign officials.
Trump's critics immediately pounced on the new story, the latest of several versions of events about a meeting for which emails were discovered between the president's eldest son and an intermediary from the Russian government offering damaging information about Trump's opponent, Hillary Clinton. Betraying no surprise or misgivings about the offer from a hostile foreign power, Trump Jr. replied: "If it's what you say I love it especially later in the summer."
Sunday's tweet was Trump's clearest statement yet on the purpose of the meeting, which has become a focal point of Mueller's investigation even as the president and his lawyers try to downplay its significance and pummel the Mueller probe with attacks, labelling the probe a one sided "Witch Hunt".
But as Trump and his allies have tried to discredit the probe, a new talking point has emerged: that even if that meeting was held to collect damaging information, none was provided and "collusion" - Trump's go-to description of what Mueller is investigating - never occurred.
"The question is what law, statute or rule or regulation has been violated, and nobody has pointed to one," said Jay Sekulow, one of Trump's lawyers, on ABC's "This Week."
Legal experts have pointed out several possible criminal charges, including conspiracy against the United States and aiding and abetting a conspiracy.
Despite Trump's public Twitter denial, the president has expressed worry that his son may face legal exposure even as he believes he did nothing wrong, according to three people close to the White House familiar with the president's thinking but not authorised to speak publicly about private conversations.
Sekulow acknowledged that the public explanation for the meeting has changed but insisted that the White House has been very clear with the special counsel's office. He said he was not aware of Trump Jr. facing any legal exposure.