Eni SpA (E), Italy 's biggest energy company by market value, Wednesday increased by 6.7% its natural gas find estimates in offshore Mozambique after completing the appraisal phase.

In a statement, Eni said it drilled and tested the Mamba South 3 well and the results "exceeded" expectations allowing it to update its estimates for the Mamba Complex and Coral gas discoveries to 80 trillion cubic feet.

Eni said it is now finalizing the development plans of this huge resource base.

The Rome-based company now plans to drill an exploration prospect, called Agulha 1, in the southern part of Area 4, where Eni is the operator, to assess the hydrocarbon potential of untested deeper parts.

Later Wednesday, Eni is slated to publish first-quarter results.