Tanzania and Uganda are among several African countries under the United Nations scrutiny for violations of sanctions against North Korea.
According to a UN panel of experts' report, Tanzania is under investigations over alleged military dealings with a North Korean firm, valued at about $12.5 million.
The UN experts said Haegeumgang Trading Corporation is reported to be repairing and upgrading Tanzanian surface-to-air missile systems and air defence radar.
"The United Republic of Tanzania has yet to respond to the panel's enquiries," the UN investigators said.
In Uganda, the eight-member panel said it will continue in its investigation into training of military and police, "in particular the Ugandan air force" by North Korea.
Further, under probe is activities of a representative of the Korea Mining Development Trading Corporation who is said to have travelled to Uganda from Syria.
The UN investigators also said they are looking into the role of the military attaché office in the North Korean embassy in Kampala.
Uganda has had diplomatic relations with the Asian country since 1963.
North Korea, under UN sanctions for its defiant efforts to build nuclear weapons, has for many years sent military trainers to Uganda.
However, in May last year, during a visit by South Korean then president Park Geun-Hye, Uganda pledged to end all military cooperation with North Korea.
"We are disengaging the cooperation we have with North Korea as a result of UN sanctions," Sam Kutesa, the Foreign minister said at the time, adding that: "Our policy is that we do not support nuclear proliferation."
The investigators' report was released two days before the UN Security Council Monday unanimously adopted US-drafted resolution to impose new sanctions on North Korea, aimed at coercing the pariah state into negotiations on its nuclear arsenal.
Last week's UN panel report said "lax enforcement" of sanctions has allowed North Korea to earn $270 million in foreign transactions since February this year.
Abetted by dozens of UN member-states, the report said, North Korea has woven a web of "evolving evasion techniques" that are undermining the goals of Security Council resolutions.
Nikki Haley, the US ambassador to the UN, recently warned that Washington would consider restricting trade with countries that do business with North Korea in violation of the sanctions.
Angola, the Democratic Republic of Congo, Eritrea, Mozambique and Namibia are also subjected to the UN investigations.
Other African countries under probe include Benin, Botswana, Mali and Zimbabwe.
North Korea is an ally of several African countries since most nations' struggle for independence in the 1960s, which it supported.