Someone over at Balloon Juice is speculating that this tweet may be Trump throwing Junior under the bus.
Just out: The big deal, very mysterious Don jr telephone calls, after the innocent Trump Tower meeting, that the media & Dems said were made to his father (me), were just conclusively found NOT to be made to me. They were made to friends & business associates of Don. Really sad!
— Donald J. Trump (@realDonaldTrump) February 1, 2019