Level 3 Communications Inc. said Monday it will acquire another top long-distance Internet carrier, Global Crossing Ltd., in an all-stock transaction valued at about $2 billion.

Both companies operate vast networks of optical fiber. Combined, they would reach 70 countries on three continents.

Global Crossing shareholders would receive 16 shares of Level 3 common stock in exchange for each share of Global Crossing common or preferred stock. Level 3 will also assume $1.1 billion of Global Crossing's debt.

After the deal was announced, shares of Global Crossing surged $11.20, or 77 percent, to $26 and Level 3 jumped 35 cents, or 24 percent, to $1.79 in premarket trading.

In 2010, the companies would have had combined revenue of $6.26 billion.

The acquisition requires regulatory and shareholder approval. The deal is expected to close before the end of the year.

Level 3 is based in Broomfield, Colo. Global Crossing is based in Bermuda, but its largest shareholder is Singapore Technologies Telemedia, which has approved the deal.

Global Crossing sought bankruptcy protection in 2002, one of many victims over overinvestment during the Internet boom.

In a separate announcement, Level 3 said it has adopted a stockholder rights plan to deter trading that would result in an ownership change. It also protects the company's ability to cite operating losses on federal tax forms.