Republican US senator Tommy Tuberville has said he will continue to block hundreds of military leadership appointments despite the Hamas attack on Israel, a close American ally, that has triggered a deadly escalation in the Middle East conflict.

Tuberville has for several months put a hold on at least 300 military nominees, which are typically confirmed in a routine manner by the US senate. The blockade is a protest over a Pentagon policy which facilitates abortions for service members and dependents.

The former Auburn University football team coach turned Alabama senator has indicated he will maintain the blockade even in the wake of Hamas’ assault on Israel, in which at least 700 mostly civilians are thought to have died, including several hundred revelers killed at a music festival, while dozens more people are believed to have been taken hostage. Israel has responded with airstrikes on the Gaza Strip that authorities in the penned-in territory say has killed at least 493 Palestinian people, including entire families sheltering in their apartments.

US military appointments currently in limbo include top officers slated to command American forces in the Middle East as well as two picks for the joint chiefs of staff. Separately, the US also does not have an ambassador to Israel, its close ally, with Democrats calling for a swift confirmation of the nominee, Jack Lew.

Joe Biden has previously called Tuberville’s stance “totally irresponsible”, and the president accused him of undermining the strength and capabilities of the US military. But the Alabama senator said on Sunday that even the attack on Israel would not shift his position.

“The Pentagon clearly thinks forcing taxpayers to facilitate abortion is more important than confirming their top nominees without a vote,” a Tuberville spokesperson told NBC. “They could end this situation today by dropping their illegal and immoral policy and get everyone confirmed rapidly, but they refuse.”

Invoking a name Tuberville calls himself because of his prior job, the spokesperson added: “If the Biden administration wants their nominees confirmed then Senate Democrats can do what Coach just did in September and file a cloture petition to force a vote.”

Military nominees are usually bundled together and confirmed by a voice vote in the Senate to speed along appointments but under the senate’s rules a single senator can hold up this process. Chuck Schumer, the Democratic Senate majority leader, has said that individual votes on each of the nominees would eat up a huge amount of time and urged Republicans to get Tuberville “in line”.

Tuberville objects to a Pentagon policy that does not itself perform abortions but provides time off and travel assistance to members of the military that require reproductive healthcare.

The US secretary of defense, Lloyd Austin, has said that the policy safeguards the healthcare and combat readiness of service members and is widely popular within the military.

Abortion has been effectively banned in several states following the US supreme court’s decision to overturn the longstanding Roe v Wade precedent last year – a move decried by progressives but lauded by conservatives like Tuberville.

“The severity of the crisis in Israel underscores the foolishness of senator Tuberville’s blockade,” said Jack Reed, a Democrat who leads the Senate armed services committee.

“The United States needs seamless military leadership in place to handle dangerous situations like this and senator Tuberville is denying it. This is no time for petty political theater, and I again urge Republican colleagues to help actively end senator Tuberville’s damaging blockade.”