The company that owns Ontario's Blue Mountain and Quebec's Mont Tremblant ski resorts will be sold for $1.5 billion US to a group that includes the parent company of the Aspen Snowmass resort.

Intrawest Resorts Holdings Inc. said Monday it has agreed to be taken over by Aspen Skiing Co. and KSL Capital Partners, a private equity firm, for $23.75 US per share in cash.

However, investors reacted to the news by sending Intrawest shares down $1.70 US, or 6.7 per cent, to close at $23.60 US on the New York Stock Exchange.

"This transaction creates significant opportunity for Intrawest and delivers tremendous value to our current shareholders," said Thomas Marano, Intrawest's chief executive officer, in a release.

He said the takeover price represents a 40 per cent premium over $16.97 US per share, Intrawest's closing stock price on Jan. 12, 2017, the trading day prior to a Reuters report speculating that the company was exploring a potential sale.

"Our new partners bring additional financial resources and a shared passion for the mountains and our mountain communities," Marano said.

The deal is expected to conclude by the end of the third quarter of this year.

In addition to Mont Tremblant and Blue Mountain, Denver-based Intrawest also owns or operates two Colorado ski resorts, Steamboat and Winter Park, plus Stratton in Vermont and Snowshoe in West Virginia. Intrawest also owns Canadian Mountain Holidays, a heli-skiing and heli-hiking company with 13 lodges in British Columbia.

Aspen Skiing Co. owns and runs Aspen Snowmass, which has four mountains — Snowmass, Aspen Mountain, Aspen Highlands and Buttermilk.

The acquisition of Intrawest is the latest move in the competition between Aspen and its big rival, Vail Resorts.

In February, Vail announced its plan to acquire Stowe Mountain Resort in Vermont for about $50 million US, and in 2016 the company bought Whistler Blackcomb for about $1.4 billion.