CALGARY, Alberta -- Canada's biggest oil and natural gas producer, EnCana Corp., said it isn't in takeover discussions and isn't aware "of any intention by any party" to make an offer for all or some of its shares.

The company also said its board and executives believe that "continued independence is the best way to create long-term value for shareholders."

The statement followed two days of heavy trading and price volatility in EnCana's stock, which is listed on the New York and Toronto stock exchanges, as investors reacted to persistent rumors that Royal Dutch Shell PLC might be preparing an offer for the company or had even had an unsolicited bid rebuffed.

Shell and EnCana did confirm Wednesday that Shell had bought 19 exploration leases from EnCana in the Beaufort Sea, offshore Alaska.