Malawian Foreign Affairs Minister Ephraim Nganda Chiume Thursday led a team of government officials on a tour of the border district of Karonga to assure people of their safety amid simmering tensions with Tanzania.

“We wanted to assure the people that their security is guaranteed,” Chiume said.

Tensions are high between Malawi and Tanzania following the latter’s claim of a substantial portion of Lake Malawi which the Tanzanians call Lake Nyasa. Tanzania resurrected the age-old territorial dispute when the administration the late Bingu wa Mutharika granted a British company concession to explore for the possibility of oil beneath the lake.

In the 1 July 1890 Heligoland (also known as the Anglo-German Agreement of 1890) Germany ceded the lake to Great Britain that colonised Malawi, then Nyasaland, while Germany gained a strategic small island near its main seaports and gave up control of its Zanzibar colony. Founding president Hastings Kamuzu Banda of Malawi and Mwalimu Julius Nyerere of Tanzania haggled over the lake again in the ’60s but Banda prevailed with the backing of Great Britain.

But the current Tanzanian president Jakaya Kikwete reportedly said the Heligoland Treaty was flawed. Dodoma went ahead to issue a new map thereby scuttling scheduled talks over the issue with Lilongwe. Pres Joyce Banda called off the talks because her Tanzanian counterpart was reneging on his earlier assurances that the two countries must talk over the territorial dispute.

Foreign Affairs Secretary Patrick Kabambe, who accompanied Chiume on the tour of Karonga, said Dodoma has reacted to Lilongwe’s protests that Malawian fishermen were being harassed on the lake and that Tanzania was sailing a gunboat on the lake ready to sink Malawian boats that would e seen on the lake.

“They say they are not aware of the harassment of fishermen but said they do routine patrols over the lake to check illegal fishing,” he said.

Kabambe also said Malawi was ready to take the issue to the International Court of Justice.