Pompeo aid tried to 'bully' ex-State Department watchdog
Democratic lawmakers present at Linick's hearing said in a joint statement that the undersecretary of state for management, Brian Bulatao, had pressured the former inspector general "to act in ways" he felt were "innappropriate", the New York Times reported.
Linick testified before both Democrats and Republicans as part of an inquiry opened by several foreign affairs committees.
Linick, who was at the centre of the investigations into the Saudi arms deal, was fired as inspector general last month at the recommendation of Secretary of State Mike Pompeo.
Bulota told Linick "that he should not pursue his investigation into whether the administration had unlawfully declared an 'emergency' last year to allow the resumption of weapons sales to Saudi Arabia".
Pompeo declared a state of emergency in May 2019 due to tensions with Iran, allowing the Trump administration to bypass Congress and sell $8.1 billion in arms to Saudi Arabia and other Arab allies, who were engaged in a war against Iran-backed Houthi rebels in Yemen.
The move infuriated lawmakers who had tried to block the sale to the Saudi-UAE bloc on the grounds of the massive civilian death toll in Yemen from US-armed coalition air strikes.
"We still have many unanswered questions," Democrats said after Linick's hearing. "Today's testimony makes it all the more critical that the administration immediately comply with outstanding requests for additional witness interviews and documents."
Several Republican senators have also voiced unease about the firing, the fourth time since the beginning of April that Trump has moved to sack an official tasked with monitoring governmental misconduct.
Pompeo has denied committing an act of retaliation by firing Linick. He confirmed to The Washington Post in May that he recommended the firing to the president and said he did not have to justify the move.
A Democratic congressional aide last month anonymously revealed 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.
Speaker Nancy Pelosi said in May that Pompeo should testify before Congress over the sacking of Linick.
"They declared a fake emergency in order to initiate the sales," Pelosi said of the 2019 sales, arguing the move had "undermined the will of Congress".
Influential Democrat Bob Menendez said last week that the Trump administration is "currently trying to sell thousands more precision-guided bombs to the President's 'friend,' Saudi Crown Prince Mohammed bin Salman".
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The government wants to conclude the sale, the details of which have not yet been made public, "even though the Saudis seemingly want out of their failed and brutal war in Yemen", he added.
Menendez, the top Democrat on the Senate Foreign Relations Committee, described in his op-ed published online by CNN how the previous contract to sell various arms to Saudi Arabia was blocked by Congress after the murder of Saudi journalist Jamal Khashoggi.
US intelligence services had concluded that the murder had been ordered by the crown prince, "a capricious Saudi despot who thinks he can butcher his critics without consequences", Menendez wrote.