The Kremlin said Thursday it regretted Russia was being dragged into the U.S. election campaign, but that relations with Washington were so poor it was unlikely to have any discernable impact on ties.

"One can only express regret," Kremlin spokesman Dmitry Peskov told reporters.

"In general, it is unlikely that this can harm our bilateral relations, because it is difficult to imagine what could push them to a level lower than the one that currently exists," he said.