President Donald Trump ranted on Twitter on Wednesday morning about the news media and its polling, about 30 minutes before the national moment of silence honoring the victims of the 9/11 attacks.

Trump blasted a new poll from ABC News and The Washington Post that found that his approval rating had slipped 6 points, to 38%.

In a follow-up tweet, he assailed polling by news organizations and said he believed he was being undercut by "fake news."

It's not the first time Trump has treated the 9/11 anniversary rather casually on Twitter.

Visit Business Insider's homepage for more stories.

President Donald Trump ranted on Twitter on Wednesday morning about the news media and its polling, about 30 minutes before the national moment of silence honoring the victims of the 9/11 attacks.

In a tweet at 8:12 a.m. ET, Trump blasted a new poll from ABC News and The Washington Post that found that his approval rating had slipped 6 points, to 38%, and that his disapproval rating had jumped to 56%.

In a follow-up tweet, he assailed polling by the "LameStream Media" and said he believed he was being undercut by "Fake News" ahead of the 2020 election.

Trump had torn into the same ABC News/Washington Post poll a day before, criticizing all polling conducted by news organizations as "fixed" and "phony."

Read more: A majority of Americans think a recession will strike in the next year — and they're blaming Trump's trade war

A moment of silence is observed every year at 8:46 a.m. ET, the moment that American Airlines Flight 11 struck the North Tower of the World Trade Center on September 11, 2001. The president and first lady Melania Trump marked the occasion on the South Lawn of the White House and later attended commemorative ceremonies at the National 9/11 Pentagon Memorial.

It's not the first time Trump has treated the 9/11 anniversary rather casually on Twitter.

On the morning of the day last year, he criticized the leadership of the Justice Department and drew attention to text messages between Peter Strzok and Lisa Page, two FBI employees who sent texts critical of Trump during a counterintelligence investigation focusing on Trump's 2016 campaign.

On September 11, 2017, Trump tweeted only twice, both times about the anniversary.