French industrial gas producer Air Liquide is buying U.S. counterpart Airgas in deal valued at about $10.3 billion.

French industrial gas producer Air Liquide is buying U.S. counterpart Airgas in deal valued at about $10.3 billion.

The companies say Air Liquide will pay $143 in cash for each share of Airgas in a deal that has already been approved by the boards of both companies. Including debt, the deal is worth 12.5 billion euros ($13.4 billion).

That represents a 35 percent premium to the closing price of Airgas shares on Monday, and the Radnor, Pennsylvania, company's stock is soaring in afternoon trading.

The acquisition still needs approval from regulators and Airgas shareholders. Airgas will become a wholly-owned subsidiary of Air Liquide once the companies complete the deal.