Twitter users were quick to notice that Karl's intentions may not have been genuine, with the Great Barrier Reef Foundation being a sponsor for the Today Show's We Love Australia trip last year.
Hugh Riminton tweeted a response to the Today host, questioning his 'principles'.
Hugh addressed Karl directly, writing: 'Dear Karl, might it have been appropriate to mention that @GBRFoundation has been a TODAY show event sponsor? There is some strength in old principles.'
Karl replied: 'Dear Hugh. There is some strength in old journalistic principles as well. To my knowledge no foundation funds have ever been used in a Today Show OB. Thanks for checking. Long live the reef.'
Karl then addressed his followers, tweeting the only concern was for the Great Barrier Reef.