A Ukrainian checkpoint has been set up near Crimea in the Kherson region in the south of the country. Troops arrived after unconfirmed reports of an attempt by Russian forces to enter the region.
Trucks lined the road waiting for the all clear to continue their journey with one driver saying he expected to wait 12 hours before being allowed to move on.
It is an example of how tension has gripped Ukraine’s frontier. Defence officials say Ukraine’s military scrambled aircraft and paratroopers to confront Russian soldiers landing on a remote spit of land between Crimea and the mainland.
The border guard service said talks between the two sides established the Russian servicemen were “guarding against possible terrorist acts” on a gas pumping station.
“At this time there is no threat of confrontation,” the Ukrainian border guard service said.