U.S. officials told NBC News on Thursday that they have been concerned for months that President Donald Trump has been discussing sensitive information on an unsecured cellphone with informal advisers, including Sean Hannity of Fox News.

The information comes after The New York Times reported that Chinese and Russian spies have been listening to personal phone calls Trump has made from his cellphones.

Several aides to Trump have repeatedly warned the president of the routine eavesdropping on his unsecure phones, The Times reported. Trump, however, has refused to give up his iPhones, the paper said.

NBC News has not confirmed aspects of that report.

The so-called experts on Trump over at the New York Times wrote a long and boring article on my cellphone usage that is so incorrect I do not have time here to correct it. I only use Government Phones, and have only one seldom used government cell phone. Story is soooo wrong! — Donald J. Trump (@realDonaldTrump) October 25, 2018

The New York Times has a new Fake Story that now the Russians and Chinese (glad they finally added China) are listening to all of my calls on cellphones. Except that I rarely use a cellphone, & when I do it’s government authorized. I like Hard Lines. Just more made up Fake News! — Donald J. Trump (@realDonaldTrump) October 25, 2018

Trump on Thursday denied the claims, calling it "soooo wrong" in a pair of tweets.

"The so-called experts on Trump over at the New York Times wrote a long and boring article on my cellphone usage that is so incorrect I do not have time here to correct it. I only use Government Phones, and have only one seldom used government cell phone. Story is soooo wrong!" he tweeted.

"The New York Times has a new Fake Story that now the Russians and Chinese (glad they finally added China) are listening to all of my calls on cellphones," Trump added. "Except that I rarely use a cellphone, & when I do it’s government authorized. I like Hard Lines. Just more made up Fake News!"

Clearly #45 memory is fading fast... He ALWAYS used his personal iPhone in WH for calls even after being told over and over again about the security risk. He disliked his secure gov issued cell- he said it was slow and “buggy” pic.twitter.com/k3ZruFWGzS — OMAROSA (@OMAROSA) October 25, 2018

The Times responded that it was confident in the accuracy of its story.

The New York Times is confident in the accuracy of our reporting. You can read our story here: https://t.co/7sEgsA0Pfh pic.twitter.com/EI9NCcMnZo — NYTimes Communications (@NYTimesPR) October 25, 2018

A former aide to Trump — Omarosa Manigault Newman — disputed his response later Thursday, tweeting that the president "ALWAYS" used his personal iPhone in the White House “even after being told over and over again about the security risk.”

"He disliked his secure gov issued cell — he said it was slow and 'buggy,'" she tweeted.