After taking a hiatus from Twitter following his controversial resignation in September, John Bolton, former Assistant to the President for National Security Affairs, is back.

Over the past week, the former United Nation’s ambassador’s name surfaced in testimony part of the ongoing impeachment probe into President Donald Trump. His name came up dozens of times throughout the hearing Thursday.

During Thursday’s hearing before the House Intelligence Committee, Fiona Hill, a former NSC aide, testified that Bolton may help answer some key questions about the administration’s dealings with Ukraine.

Further, Hill testified that Bolton “said that Rudy Giuliani was a hand grenade that was going to blow everyone up.”

Bolton has kept his distance for months, until now.

“Glad to be back on Twitter after more than two months. For the backstory, stay tuned…….” Bolton wrote. At this point, the tweet is up for interpretation as many suggest Bolton should testify as part of the impeachment proceedings.