South Korean President Park Geun-hye's approval rating has fallen to 4 percent amid a deepening political crisis, according to an opinion poll released on Friday.

Fears of policy-making paralysis prompted by the political crisis also dealt a blow to consumer confidence, which fell to its lowest in more than seven years in November, South Korea's central bank said.

Park's presidency has been rocked by allegations that a close friend used her ties to the leader to meddle in state affairs and wield improper influence. Prosecutors investigating the case have indicted, Choi Soon-sil, and are seeking to question the president about her role in the scandal.