"No, it has changed," Kohli said on his relations with the baggy green.
"I thought that was the case, but it has changed for sure. As I said, in the heat of the battle you want to be competitive but I've been proven wrong.
"The thing I said before the first Test [about being mates with Australia], that has certainly changed and you won't hear me say that ever again."
With his bombshell statement, Kohli blew Smith's traditional offer of a beer in the changerooms out of the park, leading to a tirade of abuse from a number of figures in the cricketing world.
Aussie cricketing icon Merv Hughes said he came across as a "flog", while cricket journalist Ben Horne compared his attacks against the media to Donald Trump.
Just as was looking like Kohli couldn't make another headline, the Indian captain took to Twitter to drop his latest bombshell.
The 28-year-old backtracked on his "friendship" remarks, suggesting his comments were blown up in the media.
"My answer at the post-match conference has been blown way out of proportion," he tweeted Thursday afternoon, "I did not categorically say the whole Australian team but only a couple of individuals."
Kohli said his friendship with IPL teammates at Royal Challengers Bangalore - such as Mitchell Starc - had not been tarnished.
"I continue to be in good terms with the few guys I know who I've played with at RCB that doesn't change."