US-based ERHC Energy has signed an agreement to transfer all of its rights to block 11 of the São Tomé and Principe Exclusive Economic Zone (EEZ) to Kosmos Energy.

The National Petroleum Agency of Sao Tome & Principe (ANP-STP) approved the agreement as required in the requisite production sharing contract (PSC) for EEZ block 11.

ERHC president and CEO Peter Ntephe said: "Given the difficult global environment for doing deals, particularly for deep-offshore assets in frontier areas, we are very pleased to have concluded the agreement with Kosmos.

"Given the difficult global environment for doing deals, we are very pleased to have concluded the agreement with Kosmos.

"The agreement enables us to immediately monetise one of our offshore holdings, while preserving a financial upside in the event that exploration in Block 11 is successful."

Under the agreement, ERHC will retain 100% of the rights to EEZ block 4 and also the option to acquire up to a 15% working interest in each of two other EEZ blocks of its choice that are unlicensed.

The company and the agency have agreed in principle to terms of a PSC for block 4.

ERHC holds a 35% interest in Kenya in block 11A, where it plans to spud the first exploration well toward the end of the first quarter of 2016.

In Chad, the company said it is accepting tender proposals for a 2D seismic acquisition programme for block BDS 2008.

ERHC also owns interests across several oil blocks in the Nigeria – São Tomé and Príncipe Joint Development Zone (JDZ).