US considers stopping delivery of Apache helicopters but says that it was inaccurate to suggest that aid had been suspended

The US government is considering whether to suspend a delivery of Apache helicopters to Egypt, the White House said on Tuesday, with President Obama under increasing pressure over his response to the crisis in Cairo.

Secretary of state John Kerry was due to attend a top-level cabinet meeting on Tuesday to discuss cutting aid to Egypt as it emerged that the leader of the Muslim Brotherhood had been arrested in Cairo.

At a news briefing, the White House deputy press secretary Josh Earnest said the government was evaluating the delivery of "tranches" of aid to Egypt on a "case-by-case basis", but said it was inaccurate to say that aid had been stopped.

"We're evaluating these tranches based on a case-by-case basis. We'll evaluate each one," Earnest said.

"I know that it's been publically reported that there is at some point a scheduled delivery of Apache helicopters coming up. That is an example of the kind of aid that is currently under review. A decision about the delivery of those helicopters has not been decided at this point."

The US provides $1.3bn in aid to Egypt each year and has refused to withdraw that assistance. The Department of Defense launched a review into the delivery of that aid "in all forms" on 15 August, the day after the government crackdown on two pro-Morsi protest camps in Cairo. It is yet to report its findings.

Earnest's comments contradict the statements of David Carle, a spokesman for senator Patrick Leahy, who said on Monday that the State Department and the foreign operations appropriations subcommittee had been told the "transfer of military aid was stopped".

Carle said that suspension reflected the administration's "current practice, [but] not necessarily official policy", and said there was no indication how long military assistance will be halted.

The White House denied that report, however. Earnest insisted that a review into the delivery of aid to Egypt had not yet concluded, and said it was "inaccurate to suggest that we've cut off aid to Egypt".

Pressure mounted on the US to act on Tuesday as Egypt's military-backed government continued to target the senior leadership of the Muslim Brotherhood. Mohamed Badie, the organisation's leader, or "guide", was detained in dawn raid on a Cairo apartment, while five other prominent Brotherhood leaders have already been imprisoned. About 850 people have been killed in Egypt in less than a week.

The US is yet to deliver $585m worth of aid to Egypt that is due for 2013, but has denied this is on hold, since it is not technically due to be delivered until 30 September. The sum represents almost half of the $1.3bn in aid the US provides annually. Obama has so far avoided calling the Egyptian military's overthrow of Morsi a coup, which would require the US to suspend the delivery of aid.

The US delayed the delivery of F-16 jets to Egypt at the end of July in what was scene as an implicit criticism of the behaviour of the Egyptian military since overthrowing President Morsi.

Earnest said tranches of aid had gone out since the Department of Defense announced its review. "At least some assistance has gone out. The other thing I can confirm for you is that because we have not made a decision to cut off aid to Egypt it is possible that additional tranches of aid could go out."