Fired US watchdog 'was investigating fast-tracked Saudi arms deal'
Linick, the department's most senior watchdog, was fired on Friday by Trump, who gave the vague reason that Linick no longer had his full confidence.
However, Trump's opponents immediately cried foul, saying that the dismissal was politically motivated. Congressional Democrats said Linick - whose office was critical of alleged political bias in the State Department's management - was thought to be investigating Pompeo, and launched a formal investigation.
Comment: How a legal loophole is helping Trump sell arms to Saudi Arabia
A Democratic congressional aide, anonymously revealed on Saturday that Linick was probing complaints that Pompeo misused a political appointee to perform personal errands such as dog walking and picking up laundry for himself and his wife.
Eliot Engel, the House Foreign Affairs Committee Chairman, later told CNN on Monday that "there may be another reason for Mr. Linick's firing".
"His office was investigating - at my request - Trump's phony declaration of an emergency so he could send weapons to Saudi Arabia. We don't have the full picture yet, but it's troubling that Secretary Pompeo wanted Mr Linick pushed out before this work could be completed," Engel added.
In May 2019, the Trump administration declared "an emergency" to override Congress and fast-track an $8 billion arms deal to various countries, including Saudi Arabia and the UAE.
Trump and Pompeo declared the emergency on the grounds of the need to counter the so-called "malign influence" of Iran in the Middle East.
Saudi Arabia and the UAE have been conducting a crushing offensive against the Houthi rebels in neighbouring Yemen.
Saudi air strikes - known to use US-made bombs - are thought to be responsible for the deaths of thousands of civilians, while famine and disease arising from the crisis have led to the deaths of hundreds of thousands more.
Linick, a longtime prosecutor, was appointed in 2013 by Trump's predecessor Barack Obama to oversee the $70 billion juggernaut of US diplomacy.
Senior Democrats have expressed their fury over Trump's dismissal of Linick, the fourth inspector general to be ousted by the president in the last six weeks.
Speaker Nancy Pelosi said on Saturday that Linick was "punished for honorably performing his duty to protect the Constitution and our national security".
"The president must cease his pattern of reprisal and retaliation against the public servants who are working to keep Americans safe, particularly during this time of global emergency," Pelosi said.
The White House hit back at criticism by alleging Linick was a disloyal member of a "Deep State" conspiracy attempting to oust Trump from office.
A State Department spokesperson said the new inspector general will be Stephen Akard, a former aide to Vice President Mike Pence, from his home state of Indiana.
Akard, since last year, has served as the head of the State Department's Office of Foreign Missions, which handles relations with diplomats in the US.Agencies contributed to this report.
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