MANILA - Philippine refiner Petron Corp. said on Tuesday it plans to issue P10 billion ($210 million) in bonds, half of it either this month or in June, to fund an expansion plan that could reach up to $1 billion.

The company will also issue P15 billion worth of preferred shares, Ramon Ang, chairman and CEO of Petron, told reporters after the company's annual general meeting.

Earlier, Petron said it would spend as much $1 billion on upgrading its oil refining capabilities.

"The company is planning to invest as much as $1 billion for additional facilities to enable the full conversion of residual products to more valuable gasoline, diesel, LPG and propylene," it said in a statement.