The UN's cultural organisation on Friday placed World Heritage Sites in the Ukrainian cities of Kyiv and Lviv on its "in danger" list, saying they are at risk from the war sparked by Russia's invasion.

The decision, taken at UNESCO's annual world heritage committee meeting in Riyadh, is the first step towards exclusion from the agency's World Heritage List that features 1,157 sites. 

In a statement, UNESCO said it had included Kyiv's Saint Sophia Cathedral and the medieval buildings of the city's Kyiv-Pechersk Lavra monastery site to the list "due to the threat of destruction the Russian offensive poses". 

The statement said the decision was taken because "optimal conditions are no longer met to fully guarantee the protection of the Outstanding Universal Value of the property and that it is threatened by potential danger due to the war". 

It said the two historic sites have "remained under permanent threat since the start of the invasion on February 24, 2022". 

Kyiv's Saint Sophia cathedral dates back to the 11th century and is one of the city's best-known landmarks.

Lviv, the western Ukrainian city near the Polish border, was founded in the late Middle Ages and its historic centre was inscribed on the World Heritage List in 1998.

The move came after a January decision by UNESCO to add the centre of Ukraine's Black Sea port of Odesa to the World Heritage List. 

In July, Odesa's city centre and an Orthodox cathedral were damaged in a Russian strike condemned by UNESCO.