Melania Trump has not appeared in public for 24 days and it has now been announced she will not be accompanying her husband on two key foreign trips.
US President Donald Trump is due to attend the G7 summit in Quebec this week before travelling to Singapore for a summit with North Korea's Kim Jong Un on 12 June – but his first lady will not be by his side.
Mrs Trump has not made a public appearance since 10 May when she and her husband welcomed home three Americans who had been released from prison in North Korea.
She underwent surgery on 14 May to treat a benign kidney condition and was released from hospital on 19 May.
"She will not attend the G7 and there are no plans for her to travel to Singapore at this time," her spokeswoman, Stephanie Grisham, said in an email seen by Reuters on Sunday.
The White House said the president and first lady would host a reception on Monday evening for the families of service members killed in the line of duty.
The reception is not open to the press, the White House added.
There has been much speculation about the reasons for Mrs Trump's absence from the public eye, with some claiming she had moved back to New York.
Other reports have questioned whether she is unhappy about being in the global spotlight and if the couple's relationship is rocky after adult film star Stormy Daniels alleged she had an affair with the president.
Last Wednesday, Mrs Trump tweeted in response to the news stories.
"I see the media is working overtime speculating where I am & what I'm doing. Rest assured, I'm here at the @WhiteHouse w my family, feeling great, & working hard on behalf of children & the American people!" she wrote.
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