ATHENS (Reuters) - Greece will raise the minimum wage for a second time later this year, Prime Minister Kyriakos Mitsotakis said on Thursday, as rising inflation takes a toll on consumers' income.

       The government increased monthly gross minimum wage by about 2% at 663 euros from this month.

       A second raise will be implemented from May 1, Mitsotakis told ANT1 television, according to an excerpt of an interview due to be broadcast later on Thursday.

       "I estimate that the rise in the minimum wage will be a significant one, it will be much higher than the 2% rise," Mitsotakis said.

       Surging global energy cost was the main driver of inflation that accelerated to 5.1% in December, its highest level in 11 years, data from Greece's statistics service ELSTAT showed.

       The government has spent about 1.35 billion euros in subsidies to help households and businesses with rising power and gas bills since September. Last week, it extended the financial relief into January at an additional cost of about 400 million euros.

       (Reporting by Angeliki Koutantou; editing by Grant McCool)