The White House has refused to release a photo of President Donald Trump signing a law making it easier for some people with mental illness to buy guns.
Despite repeated requests from CBS News, the White House press office has issued only a one-line response.
Mr Trump last year repealed an Obama-era rule allowing the names of certain people on mental health benefits to be entered into a criminal database.
The controversy follows a shooting by a suspect who had mental health issues.
Teen admits Florida shooting, police say
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Nikolas Cruz is accused of using a legally-purchased rifle to kill 17 people at his former high school in Parkland, Florida, on Wednesday.
In a tweet, Mr Trump called the gunman “mentally disturbed” and vowed to “tackle the difficult issue of mental health” during a speech to the nation.
But the Republican president’s critics noted his own annual budget proposed this week would cuts hundreds of millions of dollars in funding for mental health programmes.