Constitutional Court proceedings have begun against South Korea's President Park Geun-hye, despite her absence from the impeachment trial.

Politicians voted to impeach Ms Park last month over a corruption scandal, but the court must now ratify or overturn that decision.

The court's first hearing was postponed on Tuesday after Ms Park failed to appear.

The scandal has sparked mass protests demanding her resignation.

It centres on her relationship with old friend Choi Soon-sil, who has been charged with a number of offences, including abuse of power, coercion and attempted fraud.

Her lawyer previously said Ms Park, who is not legally required to attend, will not be in court "unless there are special circumstances", the Yonhap news agency reported.

Ms Park is alleged to given Ms Choi access to government decisions and allowed her to exploit their close relationship to solicit money from corporations for foundations she controlled.

Both women have apologised but deny committing criminal offences.

Separately, a judge in Denmark told the Associated Press that she was considering legal action against South Korean journalists who illegally filmed Ms Choi's daughter in court despite repeated orders not to do so.

Ms Choi's daughter, Chung Yoo-ra, a former national equestrian, was arrested in Denmark on Sunday and subsequently appeared in court, accused of overstaying her visa.

South Korean authorities say they are working on extraditing Ms Chung.

Part of the investigation into Ms Choi's activities relates to a gift horse from South Korean firm Samsung to Ms Choi, allegedly for Ms Chung's training. The prestigious Ewha Women's University in Seoul is also accused of giving Ms Chung a place based on her mother's connections.

Ms Park's impeachment case is being heard in a court by nine judges. They have 180 days to decide whether to ratify or overturn the vote in the National Assembly.

Ms Park is still formally president but has had most of her powers handed to the prime minister, who would normally have few formal powers.