Despite Donald Trump's vocal support for the U.S. oil and gas industry, it's market and global factors that have influence, sector analysis finds.

Trump from the campaign trail and through his penchant for Twitter has vowed to put the U.S. oil and gas sector at the forefront of his economic agenda, while taking a hawkish tone on geopolitical issues from China to Iran.

Trump said he'd reconsider a multilateral deal with Iran that saw Tehran forfeit some of its nuclear ambitions in exchange for relief from sanctions. That sanctions relief brought renewed interest in Iran from some of the largest energy companies in the world and, through a production arrangement penned in November, the country is the only member of the Organization of Petroleum Exporting Countries with room for expansion.

Paul McConnell, a research director at Wood Mackenzie, said there's not much a President Trump can do to contain Iran on the energy stages.

"A re-assessment of U.S. support for lifting Iranian sanctions could thus materially impact oil markets," he said in a report sent to UPI. "But the sanctions deal was a global one, and it is doubtful a Trump administration will have the clout to kill it."

On the domestic front, Trump's pressure on the U.S. automotive industry in the wake of the November election may be the hallmark of his administration's style, though McConnell said it's unclear how the broader U.S. market will evolve beyond short-term victories. On energy, Olivier Jakob, oil market analyst at Petromatrix in Switzerland, said in an emailed noted that two of the world's leading economies were showing expansions in their energy sectors before Trump was elected.

"Both the U.S. and China have shown a strong drop of production after the price collapse of the first quarter of last year," he said in an emailed note. "Both the U.S. and China are showing some recovery in production after the price recovery of the second and third quarter."

From the campaign trail, Trump pledged to make the United States energy independent and push forward with the Keystone XL pipeline, denied by the Obama administration on environmental grounds. McConnell said some of the issues related to oil and gas infrastructure could be advanced in the Trump administration, but gains elsewhere may be out of his hands.

"Oil prices will be the primary incentive rather than fiscal measures," he said.