US lawmakers directed the Pentagon to rescind its Covid-19 vaccine mandate as part of the $858 billion 2023 defense spending bill passed by the Senate on Thursday.

The mandate -- under which the Pentagon says more than 8,000 military personnel have been discharged for refusal to comply -- was scrapped over the objections of US President Joe Biden and Defense Secretary Lloyd Austin, in a victory for Republicans who sought to end it.

While various other US measures aimed at curbing the spread of Covid-19 have previously been relaxed or removed, the Pentagon's vaccine requirement remained on the basis that it protected the health and readiness of military personnel.

But the National Defense Authorization Act (NDAA) for fiscal year 2023 -- which was previously passed by the House of Representatives, and still must be signed by Biden -- now requires the defense secretary to end the mandate.

The White House supported Austin's opposition to repealing the mandate, but that was not enough to carry the day in Congress.

Republicans, who have insisted that various Covid-19 prevention measures infringe on personal freedom, pushed for the mandate's removal and had threatened to hold up the bill if it did not lift the shot requirement.

A group of Republican senators called in a late November letter for the mandate to be scrapped and for the reinstatement of those who were removed from the armed forces as a result.

The mandate has "ruined the livelihoods of men and women who have honorably served our country," they wrote, also arguing that removing troops from the military at a time when it is struggling with recruiting is detrimental.

'Myths and misbeliefs'

A proposal by Republican senators -- which would have prohibited the imposition of a new Pentagon mandate without congressional approval and required the reinstatement with back pay of personnel dismissed under the current one -- failed to pass earlier on Thursday.

The NDAA leaves the decision on potential reinstatement of servicemembers discharged under the mandate up to the Pentagon, which declined to comment on the legislation prior to its passage.

"The military departments have the ability to consider applications for reinstatement of servicemembers who were previously separated for refusing the vaccine," an explanatory statement accompanying the NDAA said.

Republican Representative Kevin McCarthy, who is seeking to become speaker of the House, has argued that the mandate has affected recruiting -- an assertion the Pentagon has questioned.

Austin said that he has "not seen any hard data that directly links the Covid mandate to an effect on our recruiting."

Deputy Pentagon Press Secretary Sabrina Singh said the mandate "appears to have very minimal impact on recruiting," and that doing away with it "would impact the readiness of the force."

Singh also said that the majority of respondents to a survey spanning from January to September 2022 said the mandate did not change the likelihood they would consider joining the military.

But General David Berger, the commandant of the US Marine Corps, said it had affected recruiting in some areas of the country, putting the blame on "myths and misbeliefs" and defending the mandate as "critical to make sure we can do our job."

© Agence France-Presse