In a televised address to the nation, South Korean President Park Geun-Hye denied some of the more lurid rumours surrounding the scandal - including reports that she had fallen into a religious cult and conducted shamanist rituals in the presidential Blue House.
It was the second time in 10 days that Park has felt compelled to speak directly to the country about the crisis that erupted last month over a close personal friend accused of embezzlement and meddling in key state affairs.
On Thursday, a Seoul court formally approved an arrest warrant for Choi Soon-Sil, Park's long-time confidante, on charges of fraud and abuse of power.
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"If necessary, I am willing to sincerely respond to prosecutors' investigations," Park said, in an at times emotional address.
"These latest developments are all my fault and were caused by my carelessness," she said, adding that she had "allowed my guard to drop" around Choi.
"I can't forgive myself ... and it is hard to sleep at night."
The scandal has shattered public trust in Park's presidency, which has more than a year left to run, triggering large street protests, calls for her resignation and a major reshuffle of her senior ministers and top advisers.
A new Gallup poll released Friday showed Park's approval rating down at five percent – a record low for any serving president.
Choi, 60, is accused of leveraging her close relationship with Park to coerce local firms into donating large sums to dubious non-profit foundations that she then used for personal gain.
Choi, whose late father was an elusive religious figure and an important mentor to Park, also faces allegations that she interfered with government affairs, including the nomination of senior officials.
Making Park a part of the investigation treads on sensitive ground, as South Korea's constitution does not allow for a sitting president to be charged with a criminal offence, apart from insurrection or treason.
But senior government officials have suggested Park could be quizzed by prosecutors as part of a general probe.
The scandal has triggered a media frenzy with fresh reports - many of them highly speculative and unsubstantiated - emerging every day, tying Choi and some of her extended family members to more alleged malpractices.
Some reports have also suggested that Choi was still involved in marginal religious group created by her father and that Park had fallen under its influence.
"There have been claims that I fell for a religious cult or had [shamanist rituals] performed in the Blue House, but I would like to clarify that those are absolutely not true," Park said in her address on Friday.
Opposition parties, while vocal in their criticism of Park's behaviour, have stopped short of calling for her resignation which would necessitate an early presidential election that they would not be confident of winning.
Analysts say Park is likely to limp on to the end of her term with her power severely undermined at a time of slowing economic growth, rising unemployment and elevated military tensions with North Korea.
