Federal Reserve Governor Jerome Powell said on Tuesday that the Fed could raise its interest rate twice this year, starting in September.

"What I would say is that, if my forecast for the economy were to be realized, and that forecast includes significantly strong growth than we've realized in the first half of the year, continued progress in the labour market and a greater basis for confidence of inflation returning to 2% goal over the medium term. If those things are realized, I feel that it will be time, potentially, as soon as September," he said.

Powell add that the second interest rate hike could follow in December.

Fed governor pointed out that he does not see a bubble in stock prices.