Tourist denies throwing her phone at air hostess.

A plane bound for Rome turned back just 20 minutes after taking off from Olbia in Sardinia following an argument with a South American passenger over her rowdy children.

The incident took place on Monday evening after flight staff asked the tourist to tell her kids, aged two and four, to sit down and wear their seat belts, reports La Nuova Sardegna.

The Volotea flight had been scheduled to depart at around 17.00 but was delayed by two hours and the children already showed "signs of being agitated" during take-off, according to Italian media reports.

After staff appealed to the woman to comply with safety regulations, the passenger launched into a heated argument and allegedly threw her cell phone at a flight attendant.

The pilot was promptly notified of the incident and decided to turn around and fly back to Sardinia where border police were waiting for the woman.

The tourist, who had been travelling to Rome Fiumicino after a family holiday in Gallura, denies all charges and claims the phone slipped out of her hand.

An investigation into the incident is underway.