Anadarko Petroluem

(APC) - Get Report

said Monday that it plans to acquire Canada's

Berkley Petroleum

for $777 million.

Anadarko, which is based in Houston, will also assume $250 million in Berkley debt. The agreement includes a right to match competing offers and a break-up fee. The boards of both companies unanimously approved the agreement.

The companies expect to close deal the week of March 12. Anadarko said the acquisition of Berkley will improve its position in Canada. Anadarko bought Union Pacific Resources, an oil and gas rival, last year for about

$4.4 billion in stock.

The acquisition plan didn't impress investors, as Anadarko lost $1.26, or 1.9%, to $64.94 in recent

New York Stock Exchange

trading.