economies last year spent $3.2 billion on their military hardware last year, an increase from the previous year, as they sought to modernise their weapons and to tackle the increasing terrorism threat.
Data from the Stockholm International Peace Research Institute (SIPRI), an independent resource on global security, shows that South Sudan and Kenya continued to be the region's top spenders on military equipment.
Juba spent $1.36 billion while Nairobi spent $954 million, up from $819 million in the previous year.
Only Uganda recorded a drop in its military spending, from $326 million in 2014 to $288 million last year.
Rwanda spent $92.9 million while Burundi, which experiencing political turmoil, increased its spending marginally from $62.2 million in 2014 to $66.4 million last year.
Tanzania, which spent $517 million, is said to have approached Russia to supply it with new weapons and military equipment.
The country has been modernising its army since 2013 as it seeks to defend its newly discovered offshore petroleum resources. In 2014, it acquired 14 new J-7Gs fighter jets, Type 63A amphibious tanks, A100 multiple rocket launchers and Type 07PA self-propelled mortars from China.
Russia's state-owned news agency RIA Novosti recently reported that the director of the Russian Military Technical Co-operation Service (FSVTS-a Russian agency established to manage military-technical co-operation between the Russia and foreign states) said that Tanzania was keen on purchasing the entire Mi-17 series of helicopters.
"Tanzania expressed interest in Russian fighter jets, small arms, tanks, anti-aircraft defence systems and armoared vehicles," FSVTS said.
It is understood that Tanzania has already made an opening bid and Russia could be considering a counter offer that will broaden the deal beyond military purchases to the Russian financing of the purchases through its state banks and an increased export market for its goods in Tanzania.
"Tanzania had carried out research into suppliers on the global weapons market. It is true that we sent Russia a bid to procure a wide range of military equipment and the negotiations are ongoing," a Tanzanian official told RIA Novosti.
Saving Air Tanzania
The EastAfrican has also learnt that Tanzania will be looking to Russian firm, Irkut Corporation to aid its struggling Air Tanzania.
The airline's chief executive, Johnson Mfinanga said the Russian firms' technical and operational characteristics meet the requirements of the programme for the development of the national carrier.
"From our memorandum of understanding, we are looking for both short and medium-range MS-21 aircraft," said Mr Mfinanga.
Air Tanzania, the default national carrier, is majority owned by the state but only has a fleet of one Bombardier Dash 8 aircraft and a leased Canadair CRJ 100s, which operates between Dar es Salaam and the Comoros islands, with local routes to Mwanza, Kigoma and Mtwara.
The Russian Industry and Trade Minister Denis Manturov said they will supply Air Tanzania with Sukhoi Superjet 100 and Yakolev Irkut MS-21 aircraft.
Kenya, on the other hand spent almost its entire military arms budget in China, purchasing $790 million worth of arms from the country. Records from SIPRI show that Kenya purchased armoured vehicles, tanks and spare parts from Beijing last year.
The increased spending came after the Cabinet Secretary Henry Rotich increased the 2015/16 allocation to the military by $170.21 million.
The purchases also signal the Kenya government's growing appetite for Chinese arms, over the past decade. The arms deals have placed China in the league of Kenya's largest sources of arms outside Russia, Germany, United States, Spain, Jordan and South Africa.
In February, SIPRI signalled that Kenya was to spend $10 million on a state-of-the-art drone from the United States in the latest effort to boost the country's combat capabilities against terrorism. The drone is expected to be delivered later in September.
"ScanEagle is intended to boost the Armed Forces' surveillance and reconnaissance capabilities. It will boost the Kenyan military's ability to gather information about terrorists in their hideouts and to stage pre-emptive attacks," SIPRI military expenditure programme director Samuel Perlo-Freeman said.
The SIPRI data shows that $288 million of the allocation was used in the acquisition of new weapons though there is no information on what kind of weapons Kampala acquired or even the source country.
"We have to enhance the capacity of Uganda's armed forces therefore specific emphasis will be placed on the acquisition of modern weaponry and strengthening intelligence capability, training and welfare," Ms Kasaija said.
Last year during the presentation of Uganda's 2015/16 budget presentation, former finance minister Matia Kasaija said that she had allocated $327.4 million to be utilized to further professionalize the armed forces.
In 2014, Kenya's military bought 18 self-propelled guns (B-52 NORA 155mm) and 15 armoured personnel carriers among a cache of heavy weapons from Serbia at a staggering cost of $260 million.