LONDON (Reuters) - Thai oil firm PTT Exploration and Production BTTE.BK extended for a third time the deadline for investors to accept its $1.9 billion offer for gas explorer Cove Energy COVE.L on Monday, as the battle with rival suitor Shell (RDSa.L) nears a conclusion.
Analysts had expected PTT to extend its offer as investors wait to see what Shell will do in the battle for Cove's huge east African gas finds. The two firms could be heading into the first formal takeover auction for a listed British company since 2008.
Britain's takeover watchdog ruled on Friday that if neither suitor declared its current offer final before 12 noon EDT on Monday, an auction would start the next day, which could see them submit bids to daily deadlines until a winner is found.
If Shell and PTT don't submit revised offers on Tuesday, their current bids will be regarded as final and there will be no auction.
PTT said the offer had been extended and would remain open until the next closing date on July 25, after it won acceptances from only 0.25 percent of Cove shares.
The two companies have been battling to buy Cove since February, attracted by the company's position in huge gas fields discovered off the coast of Mozambique which look set to transform the East African country into a major supplier of energy to Asia.
Shares in Cove have consistently traded above PTT's offer of 240 pence per share as the market bets that Shell will return with a higher offer. Shares in Cove closed on Friday at 276 pence.
Reporting by Kate Holton; Editing by Sarah Young