UPDATE 1-Teekay Tankers to offer shares to buy ship

* Says to offer 7 mln shrs of class A common stock

* Says to buy Suezmax tanker for $57 mln

June 18 (Reuters) - Tanker shipping company Teekay Tankers Ltd (TNK.N) said it planned to publicly offer 7 million shares of its class A common stock to buy a tanker from its holding company Teekay Corp (TK.N).

The company said it will grant underwriters the option to buy up to an additional 1.1 million shares to cover any over allotments.

Teekay Tankers said it would use the proceeds to buy a 2003-built Suezmax tanker for $57 million and to repay a portion of its outstanding debt under a credit facility.

The company said on buying the ship, the undrawn availability under the credit facility will increase by $58 million.

Shares of the company closed at $10.61 Thursday on the New York Stock Exchange.

For the alerts, please double click [ID:nWNAB1144] (Reporting by Arup Roychoudhury in Bangalore; Editing by Jarshad Kakkrakandy) (arup.roychoudhury@thomsonreuters.com; within U.S. +1 646 223 8780; outside U.S. +91 80 4135 5800; Reuters Messaging: arup.roychoudhury.reuters.com@reuters.net))