(Corrects paragraphs 1 and 2 to make clear final decision yet to be made)
MELBOURNE, Dec 1 (Reuters) - Royal Dutch Shell RDSa.L and PetroChina 601857.SS have taken a big step toward a long awaited gas development in Australia, signing a 27-year deal to supply Shell's Queensland Curtis Liquefied Natural Gas project.
The deal would bring to market about 5 trillion cubic feet of gas held by Shell and PetroChina's Arrow Energy in the state of Queensland, Arrow said.
"Collaboration will accelerate first gas production to approximately 2020, bringing an additional 240 petajoules per year ... of gas to the Queensland market at peak production," Arrow Energy CEO Qian Mingyang said in a statement.