The million-pound rowbarge Gloriana that had a starring role in the Queen's Diamond Jubilee river pageant has been damaged after hitting a bridge.
The ornate vessel suffered superficial damage after its two engines failed and the tide and wind carried it into Kew road bridge in west London.
A lifeboat crew from Chiswick RNLI was called out to help free the vessel, carrying four passengers, which had become wedged under the bridge.
Gloriana, a 94ft vessel decorated with gold leaf and ornately carved, harks back 200 years to when kings and queens travelled by water in opulent style.
It featured at the front of the flotilla that travelled down the River Thames last summer as part of the weekend of national celebrations marking the Queen's 60-year reign.
One report has suggested that the lifeboat crew added to the Gloriana's predicament by colliding with the barge. But a spokesman for Chiswick RNLI stressed the vessels came together in difficult circumstances as the crew battled with the tide.
He said: "There was a small impact with the Gloriana. That was because the lifeboat was trying to get itself between the Gloriana and the stone bridge. The damage was quite minor to both vessels."
He added that after the incident the Gloriana was able to berth at Kew pier.
Mark Edwards, the master boatbuilder whose team created the Gloriana rowbarge for the Queen, said he would be repairing the minor damage in the next few days.
He said: "There's a ping-pong ball-sized hole in the side but it's well above the waterline so it's not a problem. There's a small piece of wood missing from a hand rail and there's some gold leaf that needs repairing."