French oil giant Total's
Christophe de Margerie said Total is awaiting approvals for the deal to be cleared, adding it is hard to predict if the green light would come in the first or second half of 2012.
The energy firm had said as recently as Feb 10 that its deal with Inpex was just weeks from completion.
I was too optimistic, Margerie said, referring to Total's prediction last month that it was about to close the deal. It should be before the end of the year.
The agreement between the two is done. Now we are waiting for certain approvals, said Margerie, who is in Beijing for a meeting between senior Chinese government officials and global corporate executives.
Total first expressed interest in December to raise its stake in Ichthys to 30 percent from 24 percent to profit from rising demand for liquefied natural gas from fast-growing China and India and Japan in the wake of its nuclear crisis.
When asked if Total is keen to buy a stake in a Mozambique gas field run by Italian oil and gas group Eni
Are we interested? Why not? That's something we might be discussing with ENI, he said.
The Mamba gas fields in Mozambique are ENI's single most valuable project and there has been talk that the Italian firm may sell a stake in it as part of broader efforts to boost its production growth.
Margerie said Total has no plans to further boost its 27.5 percent stake in Australia's Gladstone liquefied natural gas project.
(Reporting by Koh Gui Qing, Editing by Jonathan Thatchet)