MELBOURNE, April 12 (Reuters) – Investors bet on another escalation in the bidding war for Australian miner Macarthur Coal (MCC.AX) on Monday, chasing the stock up 10 percent amid talk that coal giant Xstrata (XTA.L) could enter the fray.

Macarthur said it had yet to receive any offer from Xstrata, but this failed to hose down expectations that Xstrata could move in to trump rival bidders Peabody Energy (BTU.N), of the United States, and local coal miner New Hope Corp (NHC.AX).

The battle is fuelled by major coal miners’ desire to buy up independent coal producers in order to meet booming demand from Asian steel-makers that has driven up coal prices COAL.

Shares in Macarthur, the world’s biggest exporter of a cleaner-burning coal known as PCI, surged as much as 10 percent to A$17.17 as investors latched on to media reports that Xstrata would bid more than A$16 a share, or more than $3.7 billion.

Macarthur last week rejected an all-share offer worth $3.4 billion from New Hope and a $3.3 billion sweetened cash offer from Peabody Energy.

Key to the outcome of the bid frenzy are Macarthur’s top three shareholders — China’s CITIC Resources (1205.HK) and steel giants ArcelorMittal (ISPA.AS) and South Korea’s POSCO (005490.KS) — which have yet to say where they stand.

With the bidding war heating up and an approach to one of its shareholders from Xstrata, Macarthur last Friday deferred a vote to April 19 on its own takeover of another local rival, Gloucester Coal (GCL.AX).

The delay sparked an outcry from Gloucester’s controlling shareholder, Hong Kong-based commodities firm Noble Group (NOBG.SI), which stands to pick up a near one-quarter stake in Macarthur through the Gloucester deal.

“But let’s be clear, it appears this vote is being delayed in response to rumours, hearsay and bids that are so qualified that even seasoned professionals have no idea what is really on the table,” Noble said in release to the Singapore Exchange.

Noble said Macarthur’s top three shareholders, which together own 47.3 percent, support the Gloucester-Macarthur merger.

Macarthur said on Monday it was pressing Noble and its top shareholders to find out whether they had decided how they would vote on the Gloucester deal.

“If you do the math and add up the number of people who say they are going to vote in favour of the merger, it is a pretty simple result,” Noble said in its latest, colourful statement.

Gloucester’s (GCL.AX) independent directors said on Monday they still backed the takeover offer from Macarthur. (Reporting by Sonali Paul; Editing by Mark Bendeich)