Nortel Networks Corp., North America's biggest maker of telephone equipment filed for bankruptcy protection in Wilmington, Delaware Wednesday.

The Toronto-based company filed for creditor protection as it faced a drop in orders from telecom companies amid the global economic crisis.

Nortel's filing informed the company had more than $1 billion in assets and debt, according to Bloomberg. The globeandmail reported the firm has $4.5-billion (U.S.) in long-term debt. Nortel was due to pay a $107-million interest debt on bonds tomorrow, the source said.

Nortel's shares which soared to $1,231 (Canadian) at the peak of the tech bubble, closed Tuesday at 38.5 cents on the Toronto Stock Exchange, according to Canada's globeandmail.