"Activities are going on to purchase two submarines from a friendly country," she told Parliament while replying to a written question on her government's efforts to modernize the navy, army and air force.
Hasina didn't name the country nor the delivery date for the submarines, a report by The Daily Star said. The government already has purchased missiles, torpedoes, rocket launchers, canons, radar and other weapons for the navy.
Hasina also said a coast guard cutter would be purchased from the United States, the Daily Star reported.
The submarine purchase has been planned since a major defense report in 2009, which also pointed to buying aircraft.
The Daily Star also reported that Planning Minister Air Vice Marshal A.K. Khandker told Parliament in June that the government is looking to buy two off-the-shelf frigates, two large patrol crafts, two maritime patrol aircraft and five patrol craft for the navy.
In February 2010, Khandker said Bangladesh is considering the purchase of 80 armored vehicles and two helicopters as part of its 10-year defense transformation plan.
As part of the plan, Hasina reportedly signed in January a $1 billion deal with Russia for fighter trainers, military helicopters and anti-tank missiles.
Also in January, Hasina officially commissioned into service the BNS Padma, the first Bangladeshi-built warship, at the Titumir Naval Base, near Khunla, around 90 miles south of Dhaka.
The 160-foot frigate cost around $7.4 million and has four 37mm and two 20mm cannons, the Bangladesh Sangbad Sangstha news agency reported.
At the commissioning, Hasina said the navies of China, India and Myanmar are becoming more active in the Bay of Bengal and Bangladesh needs the Padma to protect its coastal waters.
"Our government is committed to develop a well-equipped navy in the future to protect our resources and to check arms trafficking and smuggling as well as to keep open the sea routes," she said.
During the annual 16-day Sea Thunder military exercise in the Bay of Bengal in January, the navy successfully test-fired a missile, although no details of the missile were given by the navy, a report by The Daily Star said.
The exercise, watched by Chief of Naval Staff Vice Adm. Zu Ahmed, included frigates, corvettes and patrol vessels.
The army's aviation division recently inducted two new Dauphin AS 365 N3 helicopters, the Pakistan Defense news website reported in November.
Each helicopter, supplied through Eurocopter, has a capacity of 12 passengers, a cruising speed of around 170 mph and a range of 500 miles, Pakistan Defense said.