Officials from President Joe Biden's administration are monitoring labor talks but not trying to broker a labor deal to avert an Oct. 1 strike at U.S. East and Gulf Coast ports that handle roughly half of the country's ocean imports, administration officials said on Tuesday.

Negotiations between the International Longshoremen's Association union and the United States Maritime Alliance (USMX) employer group appear to be deadlocked over pay as the Sept. 30 contract expiration approaches.

A threatened strike by 45,000 ILA-represented workers at three dozen affected ports, including New York and New Jersey, Houston and Savannah, Georgia, would send delays and costs cascading through U.S. supply chains at a time when rising costs for necessities like food, housing and healthcare have become a pivotal issue in the Nov. 5 presidential election.

"We are monitoring and assessing potential ways to address impacts to U.S. supply chains related to operations at our ports, if necessary," White House spokesperson Robyn Patterson said. "We continue to encourage the parties to continue negotiating towards an agreement that benefits all sides and prevents any disruption," she said.

The USMX, which includes container carrier and terminal owner Maersk, on Monday said the Department of Labor, the Federal Mediation & Conciliation Service and other federal agencies had reached out to the employer group.

Acting Labor Secretary Julie Su and the Department of Labor for more than a month has been in touch with the negotiating parties because establishing lines of communication is standard operating procedure, an administration official said.

Any involvement in negotiations would be at the invitation of both the union and employers.

The Biden administration has said the president does not intend to invoke a federal law known as the Taft-Hartley Act to prevent a strike at ports on the East Coast and Gulf of Mexico.

Acting on the invitation of both sides involved in last year's West Coast port negotiations, Biden dispatched Su to help hammer out a deal, which resulted in a 32% pay increase over the life of the new contract.