Malawian President Joyce Banda has said her country will take the long-standing dispute with Tanzania over Lake Malawi to the International Court of Justice for arbitration.
DW's correspondent in Blantyre, George Mhango, says President Banda decided to call for arbitration following reports that Tanzania had arrested and harassed Malawian fishermen in the disputed waters.
"I have decided to take to the International Court of Justice to determine and resolve this wrangle," Banda said, “the issue has gone too far and Malawi will seek international help to ensure that justice prevails."
She said her country had cancelled a fresh round of talks in Tanzania last month after Lilongwe discovered that Tanzania's cartographers had already redrawn the border.
"We decided to call off the follow-up dialogue meeting over the lake issue after we discovered that Tanzania had issued a new map with part of our lake."
President Banda is also concerned that Tanzania has threatened to blow up Malawian boats in the disputed waters.
"It is serious now. We have been informed by Tanzania that our boats should stop sailing on the lake otherwise they will blow them up," said Banda.
Last month's talks hosted by Malawi ended in a dead-lock after the two neighboring states said they had failed to find any common ground and differences still remained.
Malawi and Tanzania have been bickering over the largely undeveloped swathe of Lake Malawi, where Lilongwe has awarded a licence to British firm Surestream to explore for oil in northeastern waters near Tanzania.
Malawi claims ownership of the entire lake under an 1890 accord. Tanzania disputes Malawi's interpretation of that 19th century agreement and wants a halt to the oil exploration currently under way so as to pave the way for a diplomatic resolution.
Tanzanian reaction to Malawi's claims
Tanzania rejects Malawi's claims saying it's only defending its territorial integrity.Tanzania claims that 50 percent of the lake which forms its border with Malawi is part of its territory.
Tanzanian Foreign Affairs Minister, Bernard Membe, last week told reporters that "exploration activities in the northeast part of the lake should be shelved to pave way for the ongoing discussions to resolve the crisis."
Reiterating the minister's stand on the matter, Tanzania's government spokesman Assah Mwambene told DW the two neighbors can settle the matter out of court and amicably through the ongoing negotiations.
However, Mwambene also warned that any action or development within the area claimed by Tanzania will be a sign of provocation and Tanzania will react immediately.
He also denied allegations that his country had arrested and harassed Malawian fishermen.
"What we did was a routine patrol concerning the use of illegal fish nets," said Mwambene," the majority of those arrested were Tanzanians and only two Malawians."
In September 2011, the government of Malawi's late president Bingu wa Mutharika awarded a British firm, Surestream Petroleum, a licence to prospect for oil and gas on the giant lake. The company has been conducting an environmental impact assessment.
The 29,600 square kilometre(11,196 square miles) lake is Africa's third-largest freshwater lake. In Tanzania, the lake is called Lake Nyasa, which is taken from Malawi's colonial name.
In the meantime UN Secretary General Ban Ki Moon has commended Tanzania for seeking peaceful solutions in its Lake Nyasa border dispute with neighboring Malawi, insisting that dialogue is the right way to address the matter.