The Bureau of Labor Statistics data shows coal mining now employs 83,600 Americans, down from 85,200 in March.

The figures have been on a downward spiral over the past 12 months, with coal mining jobs this time last year standing at 88,500 and peaking at a high of 91,698 in 2011.

A slump in coal company profits and the resultant decline in coal mining employment have been blamed on rising natural gas prices, weaker demand and the Obama administration’s “war on coal”

Kentucky senator Mitch McConnell unveiled legislation last week aimed at streamlining the Environmental Protection Agency's coal mining permit approval process, a move he said would protect the state’s coal jobs.

“Coal is a vital part of my state’s economy and a vital part of America’s energy portfolio,” he said.

“The EPA’s attack on this important Kentucky industry hampers the growth of jobs and it especially hampers the growth of small business – the greatest engines of job creation.”

McConnell said the act was a response to more than 4000 jobs lost in the state over the last 12 months.

However, environmental group Appalachian Voices said that government policy isn’t to blame and while a downturn may have recently affected the industry, jobs during the Obama administration are 15% higher than they were during the Bush administration.

The group claimed its study of federal data showed that US coal mining employment over the past two years was the highest in 15 years.

The number of employed Americans increased by 165,000 in April, to 135,494,000 in total.