WASHINGTON (Reuters) - The chief executives of top American steel companies and related groups urged President Donald Trump on Thursday to urgently impose trade measures to curb excess steel capacity and surging imports they say are undermining the U.S. industry.

U.S. President Donald Trump salutes upon his return to the White House in Washington, U.S., from Greenbrier, WV, February 1, 2018. REUTERS/Yuri Gripas

A letter, sent to the White House and Congress by the American Iron and Steel Institute and the Steel Manufacturers Association, called on Trump to immediately act under the rarely used “Section 232” of a 1962 U.S. trade law, which allows for restrictions to protect national security.

“We urge you to implement a remedy that is comprehensive and broad based, covering all major sources of steel imports and the full range of steel products, with only limited exceptions for

products not currently available in the United States,”

according to the letter seen by Reuters.

Companies that signed the letter included Alton Steel, AK Steel Corp AKS.N, Cleveland-Cliffs Inc CLF.N, TimkenSteel Corp TKR.N, Nucor Corp NUE.N, and ArcelorMittal USA MT.AS.

The letter was the second in five months from the steel industry to Trump, who promised in his presidential campaign to protect American steelworkers from imports and ordered an investigation last April of foreign steel imports under Section 232.

The results of the investigation were handed to Trump on Jan. 11, 2018. He has 90 days to respond.

A U.S. administration official said the White House was “aware of the needs and concerns of stakeholders.”

“The president has 90 days to make his decision and we will announce that decision at the appropriate time,” the official told Reuters.

Forcing a reduction of excess production in China, which now supplies half the world’s steel, is a key goal of any potential restrictions.

The United States, the world’s biggest steep importer, and China have long been at odds over how to combat excess capacity in the global steel sector. China has argued that it has done its bit to tackle the problem by cutting capacity.

‘WAIT-AND-SEE APPROACH’

Philip Bell, president of the Steel Manufacturers Association, said there was optimism that Trump would come up with effective measures following his decision on Jan. 22 to slap tariffs on imported washers and solar panels.

“I confident he will come up with a remedy that is effective and he still has 70 days to review it and make a decision,” Bell told Reuters. “We will have to take a wait-and-see approach, but it is clear the steel industry continues to be challenged and that 232 action sooner rather than later is important.”

The letter underscored that despite the threat of trade actions, imports continue to swamp the U.S. market. In June 2017, steel imports hit their highest monthly total in more than two years by capturing 30 percent of the U.S. market, the letter said.

Efforts to address global excess capacity through international consultations and groups such as the G20 and Organization for Economic Cooperation and Development had failed, the letter added.

The European Union has warned it will retaliate if European steelmakers suffer collateral damage from import restrictions under the Section 232 investigation.

While the measure would mainly target China, NATO allies like Britain have expressed concern because the two countries have traded steel for military purposes.