The ex-wife of a groom has confessed to starting a fire at a wedding party in Kuwait in which 43 women and children died.

A 23-year-old woman told police she used petrol to torch a packed women-only wedding tent in the city of Jahra on Saturday.

She said she did it to avenge her ex-husband's ‘bad treatment’ of her before their divorce, Al-Qabas newspaper reported.

Interior ministry spokesman Colonel Mohammad al-Saber confirmed the fire was an act of arson.

'We have identified the perpetrator who confessed to committing the crime for personal reasons,' he said, without giving any further details.

The bride escaped injury in the blaze but her mother and sister were killed.

A total of 43 women and children died and 90 other people were injured in the inferno, which destroyed the packed tent in just minutes in the deadliest civilian disaster in the modern history of the Gulf state.

Last year, two women died and several others were wounded in a similar incident in Jahra, which lies 50km west of capital Kuwait City and has a population of around 500,000.

Most wedding parties in the conservative Gulf state are segregated in line with local tradition.