Fertilizer company Agrium Inc. said Wednesday it will continue to press ahead with its attempts to acquire CF Industries Holding Inc.

3-month TSX chart for Agrium Calgary-based Agrium said it remains "fully committed to acquiring CF."

"We will continue to press CF to execute a mutually beneficial merger agreement despite the fact that CF has so far ignored a clear mandate from their stockholders to conclude a transaction with us," said Mike Wilson, Agrium's president and CEO.

U.S.-based CF, which also produces fertilizer, has resisted Agrium's $3.9 billion US takeover offer and is pursuing its own hostile takeover bid for rival Terra Industries Inc.

Agrium also told investors it posted a 42 per cent drop in it second-quarter earnings.

The company said it made $370 million US, or $2.35 a share. That was down from $636 million US, or $4 a share, from a year earlier.

Agrium reported a drop of more than 87 per cent in the gross profits for its potash operations. While the volume of potash it shipped fell by 513,000 tonnes, potash prices rose by 81 per cent.

The company said it plans to provide earnings guidance for the second half of the year when it releases its third-quarter results.

"The outlook for our businesses and products remains strong and we are starting to see signs of improving demand fundamentals as we approach the fall season," said Wilson.

CF to boost bid for Terra Industries

CF said Wednesday that it is planning to boost its bid for Terra, which has rejected two earlier takeover offers.

3-month NYSE chart for CF Industries The company said it would raise its fixed exchange ratio to 0.465 shares of CF for each Terra common share. Its bid in March proposed $30.50 for each Terra share with an exchange ratio between 0.4129 and 0.4539, or about $2.2 billion US.

The sweetened offer would also return at least $1 billion US in cash to shareholders of the combined company once the proposed deal closes.

3-month NYSE chart for Terra Industries "We continue to believe firmly that a business combination with Terra is the best way to create stockholder value and is in the best interests of both CF Industries and Terra stockholders," CF's CEO Stephen Wilson said in a release.

Agrium's offer for CF is contingent upon the company dropping its bid for Terra.

Agrium shares gained $1.49 to close at $52.17 on the Toronto Stock Exchange. CF shares closed up $2.73 to $82.74 US, while Terra shares gained $1.59 to $30.44 US on the New York Stock Exchange.

With files from The Associated Press