July 22 (Reuters) - The interest rate on the most popular type of U.S. home loan crept up again last week to the highest since last August with little prospect for an immediate break for would-be homebuyers thanks to inflation-wariness among Federal Reserve officials and across bond markets.

The contract rate on a 30-year, fixed-rate mortgage rose 4 basis points to 6.69% in the week ended July 17, matching the rate last seen in the week ended August 22, 2025, the Mortgage Bankers Association said on Wednesday.

Mortgage rates have now climbed 0.60 percentage point since the U.S. and Israel launched attacks against Iran in late February, driving up global oil prices and helping drive up inflation more broadly.

After a pullback in energy costs in June amid on-again-off-again peace talks, the recent resumption of hostilities has driven them up again, and that has intensified concerns among a core of Fed officials that they may need to act to contain inflation before long through rate hikes.

"Incoming data showed that inflation dropped in June, but with oil prices spiking again, that improvement seems unlikely to continue in July data, and mortgage rates are likely to remain higher as a result," MBA Chief Economist Mike Fratantoni said in a statement.

The Fed meets next week, and while a rate hike then is still seen as an outlier probability, interest rate futures markets are broadly positioned for at least one 25-basis-point increase from the current policy rate range of 3.50% to 3.75% by year end.

More important for prospective homebuyers, though, is that rates in the segment of the U.S. Treasury market most influential in determining mortgage rates are already rising ahead of any move by the Fed. The yield on the 10-year Treasury has risen by more than a quarter percentage point since late June and ended the day on Tuesday at its highest in two months.