NEW YORK (Reuters) - Oilfield service providers will face modest hits to earnings from U.S. President Donald Trump's decision to impose tariffs on steel imports, Liberty Energy Chief Executive Ron Gusek said on Thursday.

Trump imposed 25% tariffs on steel and aluminum on March 12, and more could be coming April 2. A Dallas Federal Reserve survey on Wednesday showed executives are concerned that the levies could drive inflation in the oilfield, and raise drilling costs.

The tariffs have already pushed suppliers to raise costs on some components of the fracking process, such as perforating guns used to create tunnels to pump fluids and crack shale rocks, said Gusek, who took over the top job at Liberty after its former CEO Chris Wright was confirmed as U.S. Energy Secretary in February.

Liberty is passing those costs on to its consumers, Gusek said on a telephone interview.

"As we get a letter that says that (costs will rise), we share that letter with our customers and ask them to absorb that cost," Gusek told Reuters in a phone interview.

That, in turn, could further hit Liberty and other oilfield service providers' earnings by forcing their oil-producing customers to slow drilling activity.

Oil producers have already set their budgets for the year, so they could slow drilling activity to balance their expenses as costs for items like well casing and tubing climb, Gusek said.

One executive quoted in the Dallas Fed survey said the Trump administration's tariffs had raised costs for casing and tubing by 25% immediately, warning the knock-on effects will force producers to drop drilling rigs and decrease employment.

Gusek said he does not currently expect a slowdown in activity, noting that the guidance from Liberty's customers indicates a 2-3% hike in well completion costs.

Still, industry costs are rising, and Liberty will try to offset them by targeting more efficiency in its operations, such as by completing wells faster, Gusek said.

"Hopefully we can offset that, and the end result for our customers on the E&P side is that we can get somewhere close to holding well costs flat, even in the face of that bit of inflation."