The presidential office said assessment following the first exploratory drilling in the East Sea that the country's "Blue Whale" oil and gas prospect failed to confirm economic feasibility does not indicate an overall failure.

In a statement on Friday, an official at the top office said the latest interim outcome is not a definitive conclusion about the prospect, adding exploratory drilling of six remaining potential oil and gas reserves has yet to take place.

The official said the first exploratory drillings in general are almost never a success, referring to the case of Guyana, which undertook drilling 14 times, and the East Sea gas field, which succeeded after eleven drillings in the span of over a decade.

The office anticipated securing corporate investment in the project within the first half of this year, emphasizing that major oil companies forecast a high possibility of development.

On Thursday, the energy ministry said while partial signs of gas were detected during the initial drilling, the hydrocarbon saturation rate, a key factor in estimating how much oil and gas can be produced from a reservoir, was not enough to secure economic feasibility.