A Scots tourist has been praised for helping to save a woman who was seconds away from drowning in the River Thames.

Natalie Harrison carried out "a risky, but utterly selfless and incredible act of public service," the RNLI lifeboat crew said.

The London Coastguard requested a lifeboat after reports of a woman in the river by Bankside Pier, near Shakespeare's Globe theatre on Monday.

The crew arrived and found Ms Harrison gripping the hand of the woman in the water.

Ms Harrison was keeping the woman afloat and stopped her from drifting away in the tidal flow of the Thames.

Steve King, full-time lifeboat helmsman at Tower RNLI lifeboat station, said if it had not been for her actions, the woman in the river may not have survived.

Mr King said as the crew made their way to the scene they saw a blonde-haired figure hanging over the safety barrier and holding on to the woman in the water.

He said: "We got in close and one of the staff from the Thames RIB Experience boarded the lifeboat to help us pull the woman from the river.

"If it wasn't for Natalie's heroic efforts she may have already gone under and we might not have been able to save her."

The woman in the water, thought to be in her late 20s or early 30s, was conscious and was breathing when she was pulled onto the lifeboat, but was wet, cold and distressed.

Mr King said: "As a general rule, the RNLI doesn't encourage what Natalie did - if people enter the river or sea to try to rescue others they risk getting into difficulty themselves, which exacerbates the rescue situation for emergency services.

"We normally advise people to raise the alarm and call the coastguard.

"That said, there's no denying what she did was utterly selfless, an incredible act of public service.

"I believe she was on holiday in London and was nearby when she saw the woman in the water and acted immediately to help.

"The woman in the river was vulnerable and my fellow lifeboat crew and I feel Natalie's brave actions may well have saved that woman's life."

The RNLI is currently in the midst of its annual Respect the Water campaign, a safety initiative aimed at reducing the number of accidental drownings around the coastline and in inland waters.