LONDON — The estranged sixth wife of the ruler of Dubai asked a London court on Tuesday to protect her child from being forced into marriage, escalating a standoff within one of the world’s wealthiest royal families that has so far been cloaked in secrecy.

The wife, Princess Haya, fled with the couple’s 11-year-old daughter and 7-year-old son to London several months ago, making her at least the third woman to try to escape the palaces and estates of the ruler of Dubai, Sheikh Mohammed bin Rashid al-Maktoum.

On Tuesday, the princess made her first public appearance since then, at the opening of the closely watched legal battle.

Sitting in a wood-paneled hearing room of the family division of the high court, Princess Haya also asked for custody of the couple’s two children and a non-molestation order protecting her from violence or harassment, Britain’s Press Association reported.