Authorities have intercepted $370 million worth of cocaine on a yacht in Vanuatu that was destined for Australia.

The drugs were seized in Port Vila as part of a joint operation by Australian Federal Police, Customs, the United States Drug Enforcement Agency and South Pacific authorities.

No arrests have been made over the 750 kilogram haul - the work of a global drug syndicate operating across Australia, the US, South America and the Pacific.

Key points: 750 kilograms worth of cocaine worth $370 million

750 kilograms worth of cocaine worth $370 million Global drug syndicate operating in Australia, US, South America, Pacific

Global drug syndicate operating in Australia, US, South America, Pacific No arrests made

No arrests made Seizure part of joint operation between Australian, US, Pacific authorities

Seizure part of joint operation between Australian, US, Pacific authorities Operation targets yachts bringing drugs through the Pacific to Australia

It is one of the largest drug busts Australian authorities have been involved in.

AFP Assistant Commissioner Ramzi Jabbour says the same syndicate was behind a similar seizure of cocaine in 2011.

"Due to ongoing court processes I am limited in what I am able to say in relation to that matter," he said.

"Whilst there have been no arrests at this stage of the investigation it is an ongoing matter as I stated earlier."

Cocaine hidden behind concrete and rocks

Concealment experts from the Customs were needed to uncover the drugs stash that was hidden in compartments sealed with rocks and concrete.

The Raj had been put up for sale when the seizure was made. ( AFP )

Customs spokeswoman Karen Harfield says it was "highly sophisticated".

"The drugs were hidden in the lower engine compartments of the vessel and around the keel area," she said.

"Officers from all of the agencies spent some number of hours chiselling through the concrete and ultimately the rocks to reach the concealed drugs."

Authorities say the yacht was up for sale when the bust was made.

If it made it to Australian shores, the cocaine could have been used in more than 750,000 deals on Australian streets.

"We are well aware that international criminals see Australia as a lucrative market for their drugs, but we will continue to work closely with our partners to identify syndicates such as these, and ensure their shipments never make it to the streets of Australia," Assistant Commissioner Jabbour said.

Authorities say the cocaine worth $370 million was bound for Australia. ( AFP )

The US Drug Enforcement Administration's David Cali says the joint operation sends a strong message to organised crime groups seeking to operate in the South Pacific.

"This seizure is another fine example of the successes achieved when international law enforcement collaborates to rid our societies of the evils of drugs," he said.

Since 2010, Australian, American and Pacific authorities have been working together under Project Cringle to target drug syndicates operating in the region.

Ten people have been arrested in relation to the operation and almost two tonnes of cocaine destined for Australia has been seized.

In November last year a yacht carrying a dead body and 204 one-kilo blocks of cocaine ran aground in Tonga last year.