Istanbul, Dec 10 (IANS): Turkish President Recep Tayyip Erdogan and Bulgarian President Rumen Georgiev Radev reaffirmed the need for stronger ties during a meeting in Istanbul.

"We are in a time of severe challenges not only to the order in the Balkans but also the order in the world," said the Turkish President in a joint press conference with his Bulgarian counterpart on Friday.

"Thus, as two close NATO allies, we believe our solidarity should be increased more than ever. We agreed on the will to take the bilateral, regional, and global relationships to higher levels. We also agreed on the need to cooperate actively on the issue of irregular migration," he added.

Erdogan also signaled even-closer cooperation in some critical areas, with orders already given to increase the volume and capacity of energy and logistics between the two neighbours, Xinhua news agency reported.

For his part, Radev expressed appreciation to Erdogan for providing Bulgaria with Liquid Natural Gas to solve the country's energy shortage following Russia's decision to halt gas exports to Bulgaria.

"Our Ministry of Energy will be looking into new ways to meet Bulgaria's (energy) demand and help them out," reaffirmed the Turkish President.

Turkey and Bulgaria, sharing deep historical and cultural ties, enjoy a close relationship with a trading volume of more than $6 billion and a border gate among the busiest in the world.