US President Donald Trump on Wednesday called the US media "vicious" and "unfair" after some outlets speculated about the health of first lady Melania Trump after she underwent surgery in mid-May.

"The Fake News Media has been so unfair, and vicious, to my wife and our great First Lady, Melania," Trump tweeted.

"During her recovery from surgery they reported everything from near death, to facelift, to left the W.H. (and me) for N.Y. or Virginia, to abuse. All Fake, she is doing really well!" he added.

Trump complained in a subsequent tweet that last week "Four reporters spotted Melania in the White House ... walking merrily along to a meeting. They never reported the sighting because it would hurt the sick narrative that she was living in a different part of the world, was really ill, or whatever. Fake News is really bad!"

The rumors about the first lady's health began on May 14 when she underwent an operation known as a kidney embolization procedure to treat a "benign" renal illness, Efe quoted the White House as saying.

According to medical experts, it is normal for patients undergoing such procedures to be released the same day, but Melania remained hospitalized for almost five days.

That relatively lengthy hospitalization and the low profile she has maintained since she returned to the White House sparked all sorts of theories on the social networks, including that she had left Trump or was cooperating with Special Counsel Robert Mueller in the Russia probe.

Last weekend, Melania did not accompany Trump to Camp David and she is not scheduled to travel with the president to Quebec on Friday for the G7 summit or to Singapore in early June for his anticipated summit with North Korean leader Kim Jong-un.

The first lady, in fact, had not had any formal event on her agenda until Tuesday of this week, when she joined Trump in attending a reception for military families that was closed to the press.

Melania Trump
The White House recently said that Melania Trump is suffering from a benign kidney condition.Reuters