Ophir Energy offers to buy Salamander in SE Asia push

* Offers 0.5719 Ophir shares for every Salamander share

* Offer values Salamander at about 267 mln stg at Thursday's close

* Ophir shares fall as much as 7.1 pct; Salamander up 5.8 pct (Adds analyst comment, background)

By Abhiram Nandakumar

Nov 21 (Reuters) - British oil and gas explorer Ophir Energy (Other OTC: OPGYF - news) Plc offered to buy Salamander Energy Plc (Other OTC: SALDF - news) for 267 million pounds ($419 million) to expand in southeast Asia.

Ophir could be getting a bargain, analysts said, after a possible rival in the bidding process walked away. But shareholders might be less happy about taking on Salamander's $250 million debt, as well as the all-stock nature of the deal.

"We expect arbitrage between the two to weigh heavily on Ophir's share price," Societe Generale (Paris: FR0000130809 - news) analysts said in a note.

Salamander's shares rose as much as 5.8 percent to 96.0 pence. Ophir's stock fell as much as 7.1 percent to 167.4 pence, also hit by disappointing drill results in Tanzania.

The recent drop in oil prices has renewed appetite for deals, posing a dilemma for oil companies keen to pick up bargains but under pressure to cut costs.

A consortium led by Spain's Compania Espanola de Petroleos (CEPSA) had been considering making an offer of 121 pence in cash and one contingent value right of up to 24 pence per share for Salamander.

CEPSA said on Monday the consortium had decided not to proceed - leaving the way clear for Ophir.

BMO Capital Markets analyst David Round said the offer was "slightly disappointing". While making strategic sense for both companies, he said it fell "a long way short of previous expressions of interest".

Ophir's offer of 0.5719 shares for every Salamander share values Salamander at 266.9 million pounds, based on Ophir's closing price of 180.1 pence on Thursday.

Salamander has 259.13 million shares outstanding, according to Thomson Reuters data.

The acquisition would give Ophir an oilfield already in production off Thailand's coast and a gas development in Indonesia.

The offer is conditional on Salamander cancelling its deal with Malaysia's Sona Petroleum Bhd to sell 40 percent of two oil and gas blocks in the Gulf of Thailand.

Though almost all of Ophir's assets are scattered throughout African waters, the company has recently acquired acreage in Myanmar and Indonesia.

"They have to inject some sort of fresh momentum into what is a lacklustre story," FirstEnergy Capital analyst Gerry Donnelly said. "Africa itself, for Ophir, is getting just too expensive." (1 US dollar = 0.6377 British pound) (Additional reporting by Ron Bousso in London; Editing by Robin Paxton)