Cooperation in security, rule of law and the fight against terrorism are said to be on the agenda of FBI director James Comey and Prime Minister Boyko Borisov as the two are set to meet in Sofia.

Comey, who has been heading the Federal Bureau of Investigation (FBI) since 2013, is also set to meet several other officials, including Bulgaria's Interior Minister Veselin Vuchkov and Chief Prosecutor Sotir Tsatsarov.

He is also set to meet counterpart Vladimir Pisanchev, who heads the Bulgarian State Agency for National Security (DANS), involved mainly in counter-intelligence and anti-terrorism activities.

Apart from having been Attorney for the Southern District of New York (2002-2003) and US Deputy Attorney General (2003-2005), he has also been General Counsel and Senior Vice President of Lockheed Martin (2005-2010). The latter company has produced the F-16s Sofia has been offered as an option to have its aircraft fleet updated.

In 2013 he joined the London-based Board of Directors of HSBC Holdings, HSBC being among the four banks with which Bulgaria struck a deal to manage its global medium-term bond program worth EUR 8 B.

Comey's visit comes hours ahead of talks between Borisov and Azerbaijan's President Ilham Aliyev later on Wednesday.

Prior to visiting Bulgaria, the FBI's director was in Bucharest where he discussed cyber-security and fight against corruption with the country's leaders. The participation of Romania in NATO air policing missions was agreed during his trip there, according to AP and local media outlets.

This is the third visit of an FBI head in fourteen years.