The licence ,170 km directly south of Belgrade and within the Raska ore district, comprises one exploration permit with a surface area of 87 sq km.
Through the option Tethyan, which changed its name from Aurasian Minerals in July, can purchase 100% of the licence, or alternatively its current owner Deep Research, for €6mln cash plus mine construction costs.
Tethyan for its part has to carry out 2,000m of drilling this year, 5,000m by the end of 2018 and complete a preliminary economic assessment within six years and a fuller study in year seven.
It estimates the drill programme up until 2018 will cost £500,000.
Suva Ruda is in an area historically mined for lead and zinc but Tethyan said little exploration for copper or gold has been undertaken.
Two defined targets lie within the exploration licence: a high-grade lead and zinc veins on the edge of the Rudnitza porphyry and a well-defined porphyry dacite stock with significant copper and gold mineralisation, the 'Rudnitza' porphyry.
Peter Mullens, Tethyan Resources’ chief executive, added: “The project is centred around a dacite porphyry stock with potential dimensions of 1.2 kilometers by 0.8 kilometers.
“Within this zone of alteration several drill holes have intersected high-grade mineralisation with drill hole PDRC 04-04 bottoming in rock averaging 0.4% copper and 0.37 g/t gold.
"The outcropping mineralisation indicates that we are very high in the porphyry system and Tethyan personnel believe there is every chance of high-grade mineralisation continuing at depth.
“There is sufficient space within the alteration system to host a major porphyry copper-gold system."