He was about to give proof that he was the real Satoshi. He once announced that he will move some of Satoshi's coins (which were mined in 2009 and not moved since). But later he went back on his promise, saying that he risked arrest from law enforcement agencies, if he prove that he was the real Satoshi.
Reality is: He can't, because he doesn't have control over any of Satoshi's keys.
He doesn't even need to say that he does it. He can give some clues and hints that it is he but not show so much proof for the authorities. For example including a number on some tweets. Then moving the amount in BTC. This is just an idea.