U.S. President Barack Obama is beieved to be preparing to nominate San Francisco Federal Reserve Bank President Janet Yellen to be deputy chairperson of the Federal Reserve.

Donald Kohn, a 40-year veteran of the Fed said earlier this month he would retire in June.

According to the Reuters Thomson newsagency, Yellen is considered one of the most "dovish" members of the Fed's policymakers, who would be likely to lean toward policies that would boost growth and promote employment rather than those aimed at keeping inflation at bay.

"As bad as it looked to lose Fed Vice Chairman Kohn with his decades of experience, the FOMC is going to pick up where it left off with the experience and quiet wisdom," Chris Rupkey of the Bank of Tokyo-Mitsubishi told Reuters Thomson.

There are three seats up for grabs on the reserve board. The Obama administration has decided on candidates it wants to nominate but they are currently undergoing a screening process.