Meghan, who married the monarch's grandson in a glittering ceremony at Windsor Castle last month, travelled with the Queen by the Royal Train to northwest England for a day of events on Thursday.

The 36-year-old former American actress and star of the TV drama Suits wore a slim-fitting Givenchy cream dress, caped at the shoulders and belted at the waist. The famed French couture house's British designer made her wedding dress.

The Queen, 92, sported a lime green ensemble. Green is the colour adopted by survivors of the Grenfell Tower fire in London exactly a year ago and both royals, heads slightly bowed, observed a national silence in honour of the 71 victims.

The Queen, the world's longest-reigning and oldest monarch who has carried out thousands of engagements during her 66-year reign, appeared at ease with the newest member of the Windsors.

The pair were pictured smiling and laughing as they opened the Mersey Gateway Bridge, a new toll bridge over the River Mersey and one of the UK's biggest infrastructure projects in recent years.

They then headed to Chester, an ancient Roman city near the Welsh border, where they opened the Storyhouse, a library, theatre and cinema complex. Throughout the day, they were greeted by large crowds waving Union flags and cheering.

Perhaps indicative of how she is learning the royal ropes, at one point Meghan appeared confused over who should enter the royal car first and resorted to asking the Queen what her preference would be. Meghan then climbed in first.

Australian Associated Press