WASHINGTON, Sept 25 (Reuters) - Agriculture groups on

Wednesday urged the White House to act to avert a potential

strike that could begin on Oct. 1 at U.S. East and Gulf Coast

ports that handle roughly half of the country's ocean imports.

Dozens of groups including the American Farm Bureau

Federation, Renewable Fuels Association and American Chemistry

Council said "the time has come for the U.S. government to

intervene and ensure port operations do not stop" in order to

prevent damage to U.S. agriculture and the economy.

Republican Senator Ted Cruz raised concerns about the impact

of a work stoppage, saying the U.S. "teeters on the brink of the

first union strike among East and Gulf Coast ports since 1977."

He cited a JPMorgan ( JPM ) analysis that projected a port strike could

cost the U.S. economy $5 billion daily.

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.

The White House did not immediately comment on the letter.

"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 Tuesday, adding officials encourage continued

negotiations "toward an agreement that benefits all sides and

prevents any disruption."

President Joe Biden's administration has said the

president does not intend to invoke a federal law known as the

Taft-Hartley Act to

prevent a strike.

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.

Approximately 40% of U.S. containerized agricultural

exports move through East and Gulf Coast ports, the agriculture

groups said.