Philadelphia Federal Reserve President Charles Plosser on Wednesday said he disagreed with the Fed's decision to promise to keep interest rates low for another two years because policy should be dictated by the economy rather than a timeline.

It was inappropriate policy at an inappropriate time, Plosser told Bloomberg Radio.

Policy shouldn't be dependent on the calendar, it should be dependent on the economy, he later added.

The Fed last week pledged to keep interest rates low for at least two more years and said it would consider further steps to help growth.

Plosser was among three dissenters against the Fed's decision who wanted to avoid any specific time reference on the low-rates pledge.

(Reporting by Leah Schnurr; Editing by Theodore d'Afflisio)