Business Secretary Vince Cable met company bosses at a huge regeneration site in north Derbyshire.
The cabinet member called in at the Markham Vale site, off the M1, where he officially opened the new base of company MSE Hiller.
Derbyshire Council is investing more than £70 million towards helping to develop the former colliery site, with the aim of creating about 5,000 jobs.
The site is part of the Sheffield City Region Enterprise Zone. Companies which locate at sites in the zone are offered tax relief on major investment.
Mr Cable said: “I was very impressed by the work going on at Markham Vale.”