Verizon Communications is planning to oppose the sale of Nortel Networks Corp.’s enterprise business unit to Avaya Inc. on accounts of public safety and security concerns.

According to a court filing made on Wednesday, Verzon said that the sale of Nortel’s enterprise unit to Avaya for $475 million will threaten U.S. law enforcement, anti-terrorism and national defense interests, and if Avaya doesn’t take up Verzion’s existing contracts, then the transaction stands to face opposition from Verizon.

Avaya is scheduled to float an opening offer on Nortel's enterprise business at an auction on Friday.

And in a scenario where Avaya wins the bid, Verizon and its U.S. military, law enforcement, government, banking, business and hospital customers could be left without communications network support, causing severe hazard to the public's welfare, security and safety, Verizon said.

A Delaware judge has set an emergency hearing on Thursday to hear Verizon's concerns, which are aimed at Avaya Inc.

Verizon in the filing said it expects to reach a deal with Avaya and explores the possibility of Avaya not being the ultimate buyer of the assets.

Avaya on Thursday said it is holding talks with Verizon to reach a decree.

Nortel, once North America's biggest maker of telephone gear, filed for bankruptcy protection in January, after overweighing economic crisis foundered its turnaround efforts.