(Sharecast News) - Oil and gas outfit Amerisur Resources has taken full ownership of the Mecaya block in Colombia under new "attractive" terms that will see it pay some cash now and royalties later.The AIM-listed group relieved itself of its obligation to carry capital expenditure of approximately $8.6m in exchange for cash payments totalling $550,000 to Mecaya Oil and Gas and Petex Offshore.It will also pay the two firms royalties of 4% and 2.2%, respectively, in order to acquire a 100% interest in Mecaya, located in the Caguan-Putumayo basin.Elsewhere, Amerisur has been informed by the operator of its Indico-1 asset that drilling was "proceeding satisfactorily to plan and budget" and also highlighted that its Chiritza station project had now been commissioned, bumping the firm's capacity up to 9,000 barrels of oil per day.Chief executive John Wardle, said: "I am very pleased to have consolidated our position in the Mecaya block under these attractive terms.""The payments due to the previous partners are now, in the main, dependent upon successful production from the block, as opposed to the carry requirement we inherited by way of our original acquisition. Importantly, the increase of our working interest to 100% offers us significantly increased materiality together with wider strategic options."As of 0840 GMT, Amerisur shares had ticked up 1.68% to 9.66p.