Australian energy company Duet Group says it's considering a multibillion dollar takeover offer from the infrastructure arm of Hong Kong tycoon Li Ka-shing's business empire.

Duet said Monday that it recently received an unsolicited cash offer from Cheung Kong Infrastructure Holdings for 3 Australian dollars a share. The offer is worth A$7.3 billion dollars ($5.4 billion).

The proposal comes after the Australian government in August blocked a A$10 billion joint offer from Cheung Kong and Chinese state-owned State Grid to lease a Sydney electricity grid, citing national security grounds.

That deal was scuppered amid increasing wariness over Chinese foreign investments, particularly by state-owned companies.

Duet operates a 1,600 kilometer (994 mile) gas pipeline in Western Australia and gas and energy networks in Melbourne.