NEW YORK (AP) -- The collapse of a major joint venture between Dow Chemical and a state-owned Kuwaiti company has raised questions about Dow's continued willingness to pay $15.3 billion for Rohm & Haas Co.

The shares of both U.S. companies plunged more than 15 percent in midday trading.

Midland, Mich.-based Dow agreed in July to pay a 74 percent premium for the Philadelphia-based specialty chemical maker.

But Dow officials would not comment on Monday and it remains unclear if the world's second-largest chemical company intends to scuttle the agreement.

Kuwait's government on Sunday scrapped its planned $17.4 billion K-Dow joint venture, calling the deal "very risky" amid a global financial crisis and falling crude prices.

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