Two scandals linking the Australian weather bureau to cryptocurrency are being claimed as coincidental.

An advertising company remains suspended by the Bureau of Meteorology after ads linking to a scam article about Bitcoin appeared on the site in January and February.

The organisation's Melbourne offices were raided by federal police later in February over allegations two employees had been using the bureau's powerful computers to mine cryptocurrencies.

BoM director Andrew Johnson told a Senate hearing on Monday there was "no connection whatsoever" between the two events.

The probe into data mining had been underway for a considerable time before the Australian Federal Police made the decision to act in February, he said.

But he was unable to answer questions from Centre Alliance senator Stirling Griff about the progress of that investigation.

Dr Johnson did confirm the advertising agency responsible for the fraudulent ads in January and February remains blacklisted because of concerns about its ability to block activity.

The ads linked to a news story about Tesla boss Elon Musk on a fake CNN look-alike website which then linked users to scam Bitcoin sites.

Dr Johnson said it was a constant battle against those with malicious intent but the bureau used a four-stage review policy used to monitor ads from a second organisation.

Advertising on the site brings in around $4 million annually.