COLUMBIA, S.C. (Reuters) - South Carolina utilities said on Monday they are abandoning two unfinished reactors that were once hailed as the start of a U.S. Nuclear power renaissance before they were dogged by billions of dollars in cost overruns.

In the years since, however, a shale revolution unleashed a glut of cheaper natural gas, the Fukushima accident in Japan raised fresh safety concerns and the Trump administration is now unwinding steps aimed at countering climate change.

"We arrived at this very difficult but necessary decision following months of evaluating the project from all perspectives to determine the most prudent path forward," said SCANA Chief Executive Officer Kevin Marsh in a statement.

Summer increases the likelihood Southern Co will abandon the Vogtle project, adding to a long list of nuclear power plants canceled after construction began.

Santee Cooper's Chief Executive Officer Lonnie Carter urged the U.S. government to invest in energy and noted that the country could be caught off guard if sluggish electricity demand began to rise again.