British oil and gas explorer Emerald Energy Plc said on Monday it received a takeover approach, continuing a wave of consolidation in the sector and lifting its shares to their highest in over a decade.

The mid-cap company, which has assets in Syria, Colombia and Peru, said talks regarding the possible cash offer are at an early stage but declined to comment on the price or identity of the would-be purchaser.

Its shares rose 10 percent on Friday on speculation of an offer at around 750 pence per share, which would value Emerald at about 470 million pounds ($757 million).

The shares jumped as much as 13 percent on Monday to 635.90 pence, the highest level since October 1998, before paring gains to trade at 630 pence at 1214 GMT.

The Financial Times has said potential buyers include Canada's Gran Tierra Energy GTO.TO, which also has operations in Colombia and Peru, and Emerald's largest shareholder, Waterford Finance.

Richard Savage, an analyst at Mirabaud Securities, said Emerald's main asset is its 50 percent stake in Block 26 in Syria and added that interest from parties connected to Gulfsands Petroleum, the operator of the block, cannot be ruled out.

Another analyst, who asked not to be named, ruled out U.S buyers, saying they tend to avoid assets in Syria, but said Chinese, Indian or Canadian companies could be interested.

The oil and gas industry has seen a flurry of consolidation activity recently.

Heritage Oil agreed to a $6 billion merger with Turkey's Genel Energy, Chinese oil refiner Sinopec negotiated a $7.24 billion buy of Swiss oil explorer Addax Petroleum, and Venture Production at the weekend rejected a hostile $2 billion offer from Centrica.