President Donald Trump tweeted Sunday that he discussed forming an "impenetrable cyber security unit" with Russian President Vladimir Putin at the G-20 summit in Germany.

Trump’s tweet was the fourth in an extended series in which he discussed the G-20 summit and allegations of Russian hacking. The president called the G-20 "a great success," citing the cease-fire in Syria. Trump also said Putin had "vehemently denied" interfering in the 2016 election, a claim that was received dubiously by many quarters in the United States.

He also used two tweets to slam the Democratic National Committee and the sixth tweet to take a dig at the mainstream media.

Here are Trump’s six morning tweets, in sequence:

1. The G 20 Summit was a great success for the U.S. – Explained that the U.S. must fix the many bad trade deals it has made. Will get done!

2. I strongly pressed President Putin twice about Russian meddling in our election. He vehemently denied it. I’ve already given my opinion…..

3. ..We negotiated a ceasefire in parts of Syria which will save lives. Now it is time to move forward in working constructively with Russia!

4. Putin & I discussed forming an impenetrable Cyber Security unit so that election hacking, & many other negative things, will be guarded..

5. …and safe. Questions were asked about why the CIA & FBI had to ask the DNC 13 times for their SERVER, and were rejected, still don’t….

6. …have it. Fake News said 17 intel agencies when actually 4 (had to apologize). Why did Obama do NOTHING when he had info before election?