Nicola Sturgeon is under pressure to finally abolish her rules requiring the wearing of face masks in Scotland after being pictured without one on Tuesday at the Duke of Edinburgh's memorial service.

       Douglas Ross, the Scottish Tory leader, said the First Minister had "used her own judgment" by choosing not to wear a face covering during the 45-minute service at Westminster Abbey.

       But he said she was "treating the Scottish public like children" by refusing to grant them the same latitude. Ms Sturgeon's rules mean masks remain mandatory in most indoor public places in Scotland, including places of worship.

       The First Minister will make a statement at Holyrood on Wednesday afternoon on whether the requirement will be abolished, bringing Scotland into line with the rest of the UK.

       But there are fears she will delay the scrapping of the rule for a second time because Scotland has had the UK's highest Covid rates for several weeks, despite her tighter restrictions.

       The Office for National Statistics (ONS) has estimated that one in 11 people have the virus in Scotland in the week ending March 19. This compared with one in 15 people in England, one in 17 in Northern Ireland and one in 25 in Wales.

       SNP ministers have blamed the new, more transmissible, BA2 type of the omicron strain, claiming it had seeded in Scotland more quickly than in the rest of the UK.

       But Dr Christine Tait-Burkard, an expert on coronaviruses from Edinburgh University, has warned the effect of mask wearing "without many of the other restrictions in place is small, or it's smaller than it ever was before".

       Visitors to Westminster Abbey are advised that the wearing of face coverings during services is optional.

       Ms Sturgeon and her husband, Peter Murrell, were photographed without masks as they sat behind the Prime Minister and the Chancellor during the Duke's service.

       'Prolonging hardship of public'

       Mr Ross said on Tuesday: "Nicola Sturgeon used her own judgment to choose not to wear a mask at the Duke of Edinburgh’s memorial service this morning – yet she won’t trust Scots to do the same.

       “Instead of treating the Scottish public like children, Nicola Sturgeon must allow Scots to take personal responsibility for their own safety. I hope her choice today indicates that she will be scrapping facemask requirements in Scotland.”

       Arguing the higher Covid rates in Scotland showed her restrictions had failed, he added: "All the SNP have achieved with their dithering and delays is to prolong the hardship of the public and businesses."

       Ms Sturgeon had promised to scrap the requirement to wear face coverings on March 21, along with all other remaining legal restrictions, but she instead delayed lifting the rule indefinitely.

       She is expected to announce on Wednesday whether her mask rule will be lifted on April 4, the earliest date it could be scrapped. Businesses have warned that keeping the restriction could throw Scotland's economic recovery into "reverse gear".

       However, it emerged last week that secondary school pupils will have to keep wearing face coverings after the Easter holidays in communal areas such as corridors.