Thomson Reuters Corp on Tuesday launched a $9 billion share buyback, sending its shares higher, and said it would complete the sale of a majority stake in its Financial & Risk unit to Blackstone Group LP on Oct. 1.

Shares in Thomson Reuters, which had been suspended prior to the announcement, were trading at C$58.03, up 3.6 percent at 1:30 p.m. EDT (1730 GMT) in Toronto, having earlier hit C$58.50 after trading recommenced, their highest level since the deal was announced on Jan. 30.

The tender offer, which expires on Oct. 2, has been priced at $42 to $47 per share, an 11.5 percent premium to the stock's average price over the past 20 trading days, the company said in a statement. Thomson Reuters' U.S.-listed shares were trading at $44.94, up 3.9 percent at 1:30 p.m. EDT (1730 GMT).

The news and information provider had previously said it expected to complete the deal, which values the business at about $20 billion, in the fourth quarter of 2018.

The company reiterated its guidance that it will receive about $17 billion in gross proceeds when the deal closes, out of which it plans to return $10 billion to shareholders.

As part of that process, the company said up to $9 billion will be returned to shareholders through a tender offer for shares which commences on Tuesday.

From the remainder of the proceeds, the company said it will redeem $4 billion of debt, keep $2 billion of cash on its balance sheet and use $1 billion to cover expenses related to the transaction.

Thomson Reuters said Woodbridge, the Thomson family's investment company, would participate in the buy back and retain a 64 percent ownership in the company.