Senate Democrats are set to advance legislation this week that would effectively prevent US President Joe Biden from making good on his pledge to close the Guantanamo Bay prison, erecting the same hurdle that former president Barack Obama failed to overcome in his efforts to shutter the notorious detention site. Although Democrats control the Senate, they have opted to maintain long-standing restrictions in the annual defence authorisation bill that would inhibit Mr Biden’s ability to close the military jail. Senators are expected to vote on the legislation this week. The Biden administration released a statement this month noting it “strongly objects” to the provisions in the Senate defence bill that would bar the transfer of detainees from Guantanamo — a key tactic it has sought to employ in closing the prison. Critics around the world have long assailed the US for keeping Guantanamo open, pointing to its enormous costs and the <a href="https://www.thenationalnews.com/world/us-news/2021/09/09/seventh-guantanamo-bay-judge-tries-to-break-deadlock-in-13-year-case-against-911-five/" target="_blank">military justice system's failure </a>to score convictions against the men held there, decades after they were captured in Afghanistan and elsewhere. Congress has maintained the provisions that effectively bar the closure of Guantanamo in defence authorisation and spending legislation for more than a decade, and the latest Senate defence bill indicates that Democrats in the upper chamber are still unwilling to bring their Guantanamo policy in line with the White House. “Obviously the president’s intention is to close it, but there are a lot of details that have to be worked out before that can be done,” Jack Reed, the Democratic chairman of the Senate Armed Services Committee, told <i>The National</i>. But he noted the Senate would still need to resolve its differences over the defence bill with the House of Representatives via a conference committee that would hammer out compromise legislation for Mr Biden to sign into law. Notably, House Democrats deleted the restrictions on closing Guantanamo from their version of the defence bill, <a href="https://www.thenationalnews.com/world/us-news/2021/09/24/us-congress-votes-to-create-afghanistan-war-commission/" target="_blank">which passed 316-113 in September</a>. The House defence spending panel even <a href="https://www.thenationalnews.com/world/us-news/2021/06/30/us-congress-advances-legislation-to-close-guantanamo-bay-military-jail/" target="_blank">voted in June to defund the Guantanamo Bay prison</a>. House Democrats had previously voted to delete the Guantanamo restrictions from the defence bill under former president Donald Trump — who supported keeping the prison open — but ultimately yielded to Senate Republicans, ensuring that the limitations have remained law. And even if the White House and House Democrats convince senators to drop the restrictions from the final defence bill, it could come at the cost of Republican votes that will be needed to pass the legislation. A <a href="https://www.thenationalnews.com/world/the-americas/what-is-the-filibuster-in-us-politics-1.1199867" target="_blank">procedural mechanism called the filibuster</a> requires 60 votes to pass legislation through the Senate — meaning Democrats will need at least 10 Republican votes to pass the defence bill. Republicans largely favour keeping Guantanamo open, raising the prospect that Democrats may keep the restrictions in place to prevent a showdown over the legislation. Guantanamo Bay held about 800 inmates at its peak under former president George W Bush, who first opened the site. Mr Obama tried emptying it by transferring prisoners to third-party countries, but even progressive stalwarts such as Bernie Sanders and Elizabeth Warren voted against easing restrictions. By the end of Mr Obama’s presidency, the prison held 41 inmates — down from 242 when he took office. Mr Biden <a href="https://www.thenationalnews.com/world/us-news/2021/07/19/biden-transfers-first-guantanamo-detainee-in-bid-to-close-prison/" target="_blank">transferred his first detainee, Abdul Latif Nasser, to Morocco in July</a>, and his administration also approved <a href="https://www.thenationalnews.com/world/us-news/2021/10/14/us-approves-freeing-two-guantanamo-detainees/" target="_blank">the release of two more detainees in October</a>.