Ukrainian President Viktor Yanukovych said Thursday that coal production in Ukraine has reached its pre-crisis levels.

"Coal output in Ukraine has increased by about 15 million tons over the past three years," said Yanukovych, during his visit to the city of Donetsk in eastern Ukraine.

"In the first seven months of the year, coal production totaled 48 million tons, which was 12 percent higher than we had planned."

Yanukovych stressed that the main task for local authorities is to ensure safe and healthy work environments for miners, as 48 people died and more than 1,500 were injured in coal mine accidents across the country in the first half of the year.

Meanwhile, local authorities must ensure prompt payment of wages to miners, said the president, adding that the monthly wage for miners grew 10 percent this year to nearly 700 U.S. dollars.

Ukraine, Europe's fourth largest coal producer, is boosting domestic coal production to substitute for expensive gas. Last year, coal production in the post-Soviet country rose 4.8 percent to 85.745 million tons.

According to experts, Ukraine's coal reserves account for four percent of the world's total, which are sufficient to maintain its current production levels for about 400 years.