British Airways Stake in USAir Opposed : Airlines: Delta and American call on the government to block the proposed $750-million deal.

British Airways’ proposed $750-million investment in USAir Group Inc. was harshly criticized Monday by two big U.S. airlines.

Delta Air Lines Inc., the No. 3 ranked U.S. carrier, called on the Department of Transportation to block the deal, while No. 1 American Airlines said any agreement should be matched by a reciprocal opening of British aviation markets.

Delta charged that the investment, which would give British Airways 44% of USAir’s equity and 21% of its voting stock, effectively will put the Arlington, Va.-based airline under British Airways’ control.

“Therefore the Department of Transportation, as a matter of law, must take action to prevent consummation of this agreement,” Delta said in a statement.

Under U.S. law, foreign airlines are prohibited from owning more than 25% of a U.S. carrier’s voting stock and more than 49% of its total stock.

Delta claims the transaction would make British Airways USAir’s largest single stockholder and lead to the consolidation of some airline operations.

American Airlines Chairman Robert Crandall said in a message to employees that the government should not approve the British Airways-USAir deal “unless the U.S. secures equal access for U.S. carriers” in the British market.

Crandall listed nearly a dozen demands that he said should be met to assure competitive parity for American and other U.S. airlines.

For example, he said U.S. carriers should have increased access to London’s Heathrow Airport. British carriers are now able to serve Heathrow from 11 U.S. airports, while U.S. carriers can fly there from only eight, he noted.

Delta also called for revisions in the Anglo-American aviation agreement.

USAir spokesman David Shipley said the agreement between USAir and British Airways is “a business deal between two companies and not a political matter between two countries.”