SYDNEY (AFP) - Two Polish nationals have been charged after Australian police seized more than 1.2 tonnes of ecstasy in the country's biggest drugs haul of the year, officials said on Saturday (Oct 15).

Police put the street value of the seizure at A$145 million (S$154 million).

The men, aged 28 and 29, allegedly imported the drugs concealed within a cargo of aluminium sheets from the Czech Republic, Border Force Commander Tim Fitzgerald said.

"The goods were declared as aluminium rolls and within the aluminium rolls there was a number of lead casings that concealed the actual narcotics themselves, so it's a very sophisticated concealment," he said.

They were found at a storage facility in Sydney on Thursday after a tip-off.

"This is the largest drug haul in Australia so far in 2016 and the fourth-largest ecstasy seizure on record," said Justice Minister Michael Keenan.

"The size of this seizure and the amount of harm it would have caused cannot be understated."

He added that more arrests were expected.