Prime Minister Bill English has told Newshub there will unmanned entry to Pike River by the end of the year.

He shared the information after Newshub approached him about why he had ignored an engineering professor's personal appeal to use a high-tech robot designed specifically to enter the mine.

This robot is called "HADES". It is an "Underground Mine Scout Robot" - designed specifically to go into Pike River.

It is explosion-proof and water-resistant with visual and gas sensors. Its makers say it could get in safely.