The Calgary-based company is marketing an up to 49.9 percent stake in a package of six Mexico pipelines, excluding the recently announced $2.1 billion Sur de Texas-Tuxpan pipeline project.

The pipelines on offer are all in operation or expected to be operational by 2018. TransCanada did not specify how much it expects to make from the sale of the stake.

"The asset sales process is progressing, advisers have been engaged and the initial stage of soliciting interested parties is well under way," Chief Executive Russ Girling told analysts on a conference call, adding that the company expects to provide an update on the sales process by year-end.

The Mexico pipeline stake and the sale of the company's U.S. Northeast merchant power assets are expected to help fund the company's recently completed $10.3 billion takeover of Columbia Pipeline Group.

That deal, which closed July 1, transformed TransCanada into one of North America's largest natural gas transmission businesses, easing investor worries over the company's growth, which has been hindered by regulatory challenges on planned crude oil pipeline projects.

TransCanada has what it calls four "transformational" projects on its books, including the Energy East crude oil pipeline and the long-delayed Keystone XL expansion.

Canada's energy regulator in June officially launched its 21-month review of the C$15.7 billion ($11.9 billion) Energy East line, which would carry oil from Alberta's oil sands to refineries and export terminals in eastern Canada.

On Keystone XL, TransCanada formally requested arbitration in June over U.S. President Barack Obama's rejection of the cross-border project, seeking $15 billion in damages.

The company said it remains well positioned to fund its C$25 billion portfolio of near-term projects. Its shares were up 1.63 percent at C$60.42 on Thursday in Toronto.

Net income attributable to the company's common shares fell to C$365 million ($277.4 million), or 52 Canadian cents per share, in the second quarter ended June 30 from C$429 million, or 60 Canadian cents per share, a year earlier.

Analysts on average had expected earnings of 51 Canadian cents per share, according to Thomson Reuters I/B/E/S.

The Calgary-based company's revenue rose 4.6 percent to C$2.75 billion.

(Reporting by Julie Gordon in Vancouver, Additional reporting by Amrutha Gayathri in Bengaluru; editing by Sriraj Kalluvila and Phil Berlowitz)

By Julie Gordon