Mexican conglomerate Alfa Sab de CV and Harbour Energy Ltd have agreed to acquire Canadian oil and gas company Pacific Rubiales Energy Corp for C$6 billion ($4.97 billion), including debt,. Pacific Rubiales is the largest independent oil and gas producer in Latin America. Its shares have plummeted more than 80 percent since oil prices began to slide last summer. Alfa, which already owns a 20 percent stake in the company, decided now was the time to act, and on vastly improved terms than when it paid C$21 per share last August in a C$189.4 million transaction to raise its stake in the company to 17 percent. Toronto-listed Pacific Rubiales, whose shares also trade in Colombia, suspended trade in its Bogota shares on Tuesday afternoon after the deal was made public. Alfa and Harbour have agreed to pay around C$6 ($5) per share for Pacific Rubiales and will each own half of the company, that source said, asking not to be identified because the deal is not yet public. Pacific Rubiales ended trading on Tuesday at C$4.83. Harbour Energy is a joint venture between Asian commodity trader Noble Group Ltd (NOBG.SI) and U.S. private-equity firm EIG Global Energy Partners. Alfa believes the investment, by boosting its oil and gas footprint, will position it to participate more strongly in Mexico’s energy liberalization, the person added.