Blantyre - Malawi and its northern neighbour Tanzania have agreed to revive talks to resolve a long-running border dispute, President Peter Mutharika said on Tuesday after meeting Tanzania's foreign minister in Lilongwe.The two east African neighbours are at odds over the ownership of Lake Malawi which straddles both countries with Tanzania claiming the top half of Africa's third largest freshwater lake - a claim contested by Malawi."The mediation efforts will be resuscitated towards a logical conclusion of the Lake Malawi border dispute," Mutharika said in a statement. Mediation to resolve the dispute has been stalled since 2012, but will be revived under the supervision of former Mozambican president Joaquim Chissano. Tanzanian foreign minister Augustine Mahiga told journalists after meeting Mutharika that "the lake issue has festered for some time", confirming the resumption of talks under Chissano.The 54-year-old dispute stems from colonial-era border lines drawn around the 29 600 square kilometres of Lake Malawi.Major tourist attraction The lake is in the Great Lakes system stretching along the East African Rift and is a major tourist attraction that straddles one third of Malawi.Based on an 1890 colonial accord, Malawi claims ownership of the whole of the lake except for a portion controlled by Mozambique. Tanzania insists that half the lake falls within its borders and blames maps drawn up by British and German authorities for the dispute."The British and the Germans left different kinds of maps that show the border in between," Mahiga said. "It is not a new map, but it is an inherited map which I think needs clarification."The border dispute resurfaced after Lilongwe in 2011 awarded British company Surestream Petroleum a licence to drill for oil and gas on the northern part of the lake.Tanzania has in the past demanded that Malawi should halt exploration activities to allow for a diplomatic solution.