In an interview published on Friday Yellen said that although wages had gone up significantly, there were substantial price increases important to people, as such increases in a relatively short period of time were very noticeable.

"They see it when they shop for food," she added. "They see it in terms of rentals. With higher mortgage rates, it's tough for young people who would like to buy a house to enter the market."

In the 12 months through April, US CPI increased 3.4% after climbing 3.5% in March. Early this month, the U.S. central bank left its benchmark overnight interest rate unchanged in the current range of 5.25% to 5.50%, where it has been since July.

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