KIEV, December 31. /TASS/. The Kakhovka-Titan high-voltage transmission line, which transmits electric power from Ukraine to Crimea, has been shut down after its protective equipment had gone off, an official at Urkenergo, the national operator of the power grids said on Wednesday night.

"Specialists are probing into why the protective system in (the town of) Kahkhovka went off," an official said.

Kakhovka-Titan is the only functioning overhead high-voltage transmission line of the four lines, which Ukrenergo used to deliver electricity to the customers in Crimea before the end of November.

An agreement on deliveries of electric power from Ukraine to Russia’s Crimean Federal District expires on Thursday, December 31.

Ukrainian Prime Minister Arseny Yatsenyuk said on Tuesday the issue of electricity supplies to Crimea was to be examined by the National Defense and Security Council.

"Power engineering is related to the sphere of national security and that’s why the issue of deliveries to Crimea should be taken up by the National Defense and Security Council," he told a major news conference.

The leader of a radical nationalistic faction of the Crimean Tatars, Mustafa Cemilev said earlier prolongation of the agreement on supplies of electricity to Crimea could be possible only if the peninsula was termed ‘the Autonomous Republic of Crimea’, the name it had before reunification with Russia in March 2014, not the Crimean Federal District which it is now.

Cemilev also put forward a number of other conditions, saying President Petro Poroshenko had agreed with them. Poroshenko also allegedly said the transmissions of electricity to Crimea would unless these conditions were observed.

On the night from November 21 to November 22, Crimea was disconnected from Ukraine’s power grids when the pylons of the high-voltage transmission lines leading to the peninsula were blown up on the territory of the neighboring Kherson region. The subversive act was organizers by the extremists standing behind the so-called blockade of Crimea.

Later on, Cemilev said however his faction agreed to the launch of one of the transmission lines for the needs of the social sphere.