Tuesday's cases are nearly double the previous high of 514 recorded on Monday.

Hospitalisations in the capital have also increased in the past day, rising from 11 to 13, however the number of patients in intensive care has dropped from two to one.

One patient is also on a ventilator.

Ms Stephen-Smith said the federal government should use its buying power to purchase more rapid tests to help current outbreaks across eastern states.

"I think it's really disappointing," she told ABC Radio on Tuesday.

"I know colleagues in other jurisdictions have pointed out that free rapid antigen tests have to be part of this response.

"Everyone expected the commonwealth would take on this responsibility because they are the ones with the biggest purchasing power. They are going to need to do more."

The ACT secured one million rapid tests from NSW at cost, which will be provided from January 17.

Large queues were seen at testing sites across Canberra, with some being turned away due to capacity being reached.

One of the ACT testing clinics in the city's north was closed on Tuesday due to a power outage resulting from a storm on Monday night.

ACT health authorities said 3485 tests were conducted at government-run clinics.

The testing number is expected to be higher once private clinics are taken into account.

Australian Associated Press