MANILA—A US senator has slammed the Philippine government for threatening to impose visa requirements for Americans after he sought to ban Filipino officials involved in the imprisonment of Sen. Leila de Lima.

"The Duterte regime should stop threatening the travel of these Filipino Americans and so many others who travel between our nations," US Sen. Richard Durbin of Illinois said in a statement released Tuesday (Manila time).

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The US lawmaker also called on the Philippine government to "release or give a quick and credible trial" to De Lima, a known critic of President Rodrigo Duterte’s anti-illegal drug campaign.

"This strong-arm tactic is an insult to the Filipino American community and the country's democracy," he added.

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De Lima, Durbin said, had been jailed for more than 1,000 days on "questionable charges."

"Her release, which has been championed by groups such as Amnesty International – and now the US Congress – is unfortunately symbolic of the larger price one increasingly pays for peaceful dissent and honest journalism under President Duterte in the Philippines," he said.

In his statement, Durbin also expressed support to Filipina journalist Maria Ressa who reportedly face harassment "for fostering honest coverage regarding the country's sweeping extra-judicial killings, which is an affront to the cherished democratic norms we share with our long standing Filipino allies."

De Lima's detention was included in provisions of the US government's $1.4-trillion 2020 budget signed by US President Donald Trump earlier this month.

A provision in the budget on “Prohibition on Entry” allows US Secretary of State Mike Pompeo to bar foreign government officials from entering the US if he has "credible information" on their involvement in the "wrongful imprisonment" of De Lima.

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Malacañang responded by banning Durbin and US Sen. Patrick Leahy of Vermont from entering the country and threatening to impose visa requirements on US citizens visiting the Philippines. US citizens currently enjoy 30-day visa-free stay in the country.

De Lima has been detained since Feb. 2017 over allegations that she received payoffs from jailed drug lords during her time as justice chief. She has repeatedly denied the allegations, blasting her detention as "political persecution."

With reports from TJ Manotoc, ABS-CBN News