Police in Perth have confiscated 320 kilograms of methamphetamine worth $320 million, as well as $1.2 million in cash, in what has been described as WA's largest ever ice seizure.

The drugs were seized in a joint operation yesterday between WA Police and the Australian Crime Commission.

Arrest warrants were executed at three residences, in Canning Vale and the Perth CBD.

Most of the drugs, about 316 kilograms, were found hidden in packages of Chinese tea at a house in Canning Vale.

An apartment on Adelaide Terrace and a hotel on Hay Street in the city were also raided.

Four Hong Kong nationals, ranging in age from 19 to 26, have been charged over the seizure.

Three of those men are believed to have been in Australia illegally, the fourth was on a visa.

The four men have already appeared in court and were remanded in custody.

Haul a 'hammer blow' to criminals, Keenan says

Federal Justice Minister Michael Keenan said it was a significant haul.

Detective Constable Rebecca Brandham shows off some of the drugs and cash seized in Perth. ( Supplied: WA Police )

"This latest seizure, this largest seizure in Western Australian history, is an example of the dividends that are being paid by the unprecedented cooperation between Commonwealth and state law enforcement," he said.

"They have taken at least 320 kilograms of this terrible drug off the streets. That would have equated to 3.2 million individual hits of ice, with a street value of upwards of $320 million.

"This seizure is a hammer blow for the organised criminals who peddle in ice."

Police said they feared what could have happened if the drugs had not been confiscated.

"[It] can only be described as frightening that this was going to hit our streets, this was going to be taken by members of our community," WA Police acting deputy commissioner Michelle Fyfe said.

WA Police Minister Liza Harvey said the operation would put a significant dent in the ice market.

"I cannot tell you the impact that will have on the families, and the relatives and the friends of the meth addicts who wreak havoc on our community," she said.

String of drug busts

This is the third major methamphetamine bust in the state in the past couple of months.

In August, police arrested three men and impounded a yacht off Western Australia's north-west coast after seizing more than 20 kilograms of methamphetamine from a unit in Perth.

Officers from the Australian Federal Police and Organised Crime Squad seized the drug — also known as ice — and almost $1 million from the Perth unit as part of a National Anti-Gang Squad operation.

They also found 11 guns, including a sawn-off shotgun and a homemade machine gun.

In July, methamphetamine with a street value of $21 million was seized along with $100,000 cash.

Five people from WA, Queensland and New South Wales were charged over the seizure in the northern Perth suburb of Karrinyup.