ATLANTA, Sept. 29 (Reuters) – Delta Air Lines said on Monday that it has closed $2.1 billion of financing deals that have bolstered its liquidity by $600 million.

The company said the transactions also have addressed more than 40 percent of its 2010 debt maturities.

Delta said the financing deals were secured by liens against its Pacific route authorities, slots and gate leaseholds.

After refinancing $1.5 billion from bank credit and revolving credit facilities of its Northwest Airlines subsidiary, Delta said it will generate $600 million in incremental liquidity.

Atlanta-based Delta, which had announced debt offerings in recent weeks, became the world's largest airline when it bought Northwest last year.

Meanwhile, AMR Corp.'s American Airlines said on Monday that its share sale generated $400 million, while US Airways Group Inc. raised $137.3 million in net proceeds from its share sale after fees and costs.

Fort Worth, Texas-based American said it issued about 48.49 million common shares at $8.25 a share, while Tempe, Arizona-based US Airways said it issued about 29.02 million common shares at $4.75 a share.

The proceeds would be used for general corporate purposes, US Airways said. Citigroup, the underwriter of US Airways's offering, exercised its over-allotment option to buy an additional 2.7 million shares.

Some US airlines have sold shares, debt or both in recent weeks to shore up their liquidity positions.

The closing of both share offerings was announced after the bell on Monday. US Airways shares fell 2 cents to $4.94 on the New York Stock Exchange. American also lost 2 cents and traded at $8.

American also completed the sale of $460 million in 6.25 convertible senior notes due 2014. The notes can be converted into common shares at any point before the maturity date of Oct. 15, 2014.