Major oil producers must take "the right steps" to ease supply concerns that have lifted crude prices to a four year-high, the head of the International Energy Agency told Reuters on Thursday.

"It is now high time for all the players, especially those key producers and oil exporters, to consider the situation and take the right steps to comfort the market, otherwise I don't see anybody benefiting," IEA Executive Director Fatih Birol said in a phone interview.

A rise in oil prices to more than $85 a barrel coupled with concerns over global trade are putting heavy pressure on emerging economies, he said.

"Expensive energy is back at a bad time for the global economy," Birol said.

(Reporting by Ron Bousso; editing by Jason Neely)