On August 10, army chief of staff General Celestin Mbala, alerted the government to an "incursion by the Angolan navy" into Congolese waters off the coast of Moanda and two other territories near the border with Angola.

Angola "expressly and categorically denies this information," the letter said.

"(It) is keen to emphasise that its armed forces did not undertake any incursion into the DRC's territorial waters, or into the areas of Tshela, Moanda and Songololo."

Luanda "vigorously condemns the publication of such groundless information aimed at undermining the excellent relations between the DRC (Democratic Republic of Congo) and Angola," it continued.

Angola reaffirmed its support of the "good neighbour policy" between the two states and its "unequivocal respect for the borders and sovereignty" of both countries, the letter stated.

A DR Congo-incorporated fishing company called Bosa has accused the Angolan navy of boarding its vessels 42 times over the past six years even though, it said, they had not strayed from DR Congo waters.

In order to avoid similar incidents in future, Angola said it hoped prevention and surveillance measures would be beefed up "to safeguard goodwill between the two countries."