The Princess Royal will cut the steel for Britain's biggest new warship to mark the start of construction work.
She will perform the "steel cut" on the main hull of the ship, the first of two in the Queen Elizabeth class, at BVT Surface Fleet Ltd shipyard in Govan, Glasgow, which is one of a number of shipyards around the UK.
SNP MSP for Govan and Scotland's deputy first minister Nicola Sturgeon will also attend the steel cutting.