MUNICH/FRANKFURT (Reuters) - Two of the world's biggest renewables players on Wednesday warned of challenges for the U.S. offshore wind sector under a presidency led by Donald Trump, flagging potential delays for the technology slammed by the president-elect.

The comments by Germany's RWE, the world's No. 2 offshore project developer, and Siemens Energy, the biggest maker of offshore wind turbines, reflect a sobering view of Trump's expected impact on renewables after his victory in this month's presidential vote.

"Given the results of the U.S. elections, we see higher risks than before for the timely implementation of offshore wind projects there," RWE finance chief Michael Mueller told journalists after presenting nine-month results.

"We have to expect that investments in our projects will come later than originally planned," he said.

Christian Bruch, CEO of Munich-headquartered Siemens Energy, also pointed to looming issues in offshore permitting in the U.S. in the future, assuming current projects that had already secured permitting would be unaffected.

"Those would be projects slated for '29, '30, '31," he told journalists after also presenting full-year results that included an upgrade of the company's mid-term targets, causing shares to reach a fresh record high.

Trump's potential impact on clean energy technologies has been squarely in focus by investors, who fear he could repeal parts of current President Joe Biden's Inflation Reduction Act, a scheme aimed at attracting investments into solar, wind and hydrogen.

In response to the cooling environment for offshore and hydrogen, where investors have become more reluctant over potential regulatory changes, RWE unveiled a 1.5 billion euro ($1.59 billion) share buyback as a smarter way to spend its cash.

Trump earlier this year singled out offshore wind as a technology he would target once in office, causing shares in Orsted, the world's biggest offshore wind project developer, to plunge.

($1 = 0.9413 euros)