FILE PHOTO: A rocket is launched from the Bulgarian navy frigate "Drazki" to simulate an attack on a mock submarine, during the BREEZE 2014 military drill in the Black Sea July 11, 2014. REUTERS/Stoyan Nenov/File Photo

SOFIA (Reuters) - Italy’s Fincantieri, German shipyard Luerssen and Bulgaria’s MTG Dolphin are expected to file bids in a tender to build two patrol ships for the Bulgarian navy, a senior official said on Tuesday.

The Black Sea country is looking to replace its three aging Soviet-made patrol ships with the new vessels and has set April 16 as the deadline for bids.

It raised the budget for the new ships by 20 percent to 984 million levs ($567 million) last year after a previous tender collapsed over financial terms.

Rear Admiral Mitko Petev, commander of the Bulgarian Navy - which also has three Belgian frigates - said the patrol boats would be equipped with weaponry for air and underwater combat and helicopter landing platforms.

He told public television BNT that Luerssen, Fincantieri and MTG-Dolphin had expressed interest in the tender.

Bulgaria plans to spend about 4.5 billion levs in the next ten years to upgrade its armed forces with new ships, fighter jets and combat vehicles.

Sofia hopes to seal a deal this summer with the United States for eight F-16 fighter jets to replace its aging Soviet-made MiG-29s and improve compliance with NATO standards.

($1 = 1.7354 leva)