Victims of the Glasgow helicopter crash have been remembered at a service in the city's cathedral, as the rescue and recovery operation continues at the Clutha pub continues.
Scottish Justice Secretary Kenny MacAskill and Deputy First Minister Nicola Sturgeon were among those in attendance.
More top news
Mr Robertson has only been in post for three years and will leave the company at the end of June.
Outbreaks of rain will spread across Scotland but a decent day in prospect for England and Wales.
The order applies to two projects to replace 51 miles of fence in two areas on the Mexican border.