Australian iron ore miner Fortescue Metals Group Ltd on Thursday terminated several senior executive positions but denied it was in response to a sharp downturn in ore prices.

"There have been a small number of changes to our senior management," Byron Value, a company spokesman, told Reuters.

"This is part of the normal evolution of our business and not a reaction to the market environment or performance related," he said.

Fortescue is the third Australian iron ore mining company to cut its senior staff in less than two weeks.

Last week BC Iron reduced the size of its board to five directors from eight and pledged to lower its directors' fees beginning Jan. 1 in a display of "responsible management".

Atlas Iron Ltd on Tuesday cut its board to six members from eight and reduced directors' fees by 15 percent.

Iron ore prices have halved in 2014 to the lowest in more than five years as the top producers Vale, Rio Tinto (Xetra: 855018 - news) and BHP Billiton (NYSE: BBL - news) flood the market with millions more tonnes of ore, hurting smaller competitors.

Iron ore stood at $69.50 a tonne.

Rio Chief Executive Sam Walsh last week labelled iron ore mining in the current climate survival of the fittest and said there were no plans to slow production.

"These moves by smaller miners are in direct response to the oversupply brought on by the majors," said Gavin Wendt, senior resources analyst for industry consultants MineLife.

Fortescue, a 155 million-tonnes-per-year producer in Australia, has already said it was halving its capital spending for the 2015 financial year.

Executives in charge of shared services, procurement and security at Fortescue were terminated, according to the spokesman. (Reporting by James Regan; Editing by Ryan Woo)