Shares in Aurora Oil and Gas have soared by more than 56 per cent after Canadian oil company Baytex Energy launched an aggressive $1.8 billion takeover bid.

Baytex has made a cash offer to acquire 100 per cent of Aurora shares for $4.10 each, which is a 52 per cent premium on its share price for the week up to February 6.

Analysts say Baytex’s offer is above consensus price targets of $3.80 per share, and other potential suitors are unlikely to outbid the Canadian company.

The offer values the US-focused producer and explorer at $1.84 billion, compared to its market value of $1.18 billion when trading closed on Thursday.

Aurora shares were up $1.465, or 56 per cent, at $4.085 at 1509 AEDT.

The offer also sparked takeover speculation about fellow US-focused oil and gas play Sundance Energy, pushing its shares 10.6 per cent higher to $1.06.

Aurora has already entered into a scheme of implementation deed with Baytex and the company’s board of directors has recommended the offer to shareholders who will vote on the deal in late April or early May.

Chairman Jon Stewart said the deal was in the best interest of shareholders, given the premium on offer.

Aurora is listed on both the Australian and Toronto stock exchanges, and focused on developing and producing oil and gas in Texas’ Eagle Ford Shale.

If the deal goes ahead Aurora will be delisted from the Australian sharemarket, becoming a subsidiary of Baytex.

Patersons oil and gas analyst Alexis Clark said the only other likely potential bidder for Aurora would be joint venture partner Marathon.

“But given the price that’s being paid Marathon is unlikely to trump that bid,” Mr Clark said.

Aurora had been a standout success story going from a $40 million company in 2010 to a $1.8 billion stock, he said.

“The next likely takeover candidate is Sundance Energy given its portfolio of assets in liquid rich plays throughout the US including the Eagle Ford,” he said.

The Aurora deal is subject to approval from Australia’s Foreign Investment Review board.