Spring is typically a busy time for home sales as the weather warms up and families prepare to move before a new school year. But the season has started out sluggish, as would-be buyers face higher mortgage interest rates and elevated prices.

Despite the brief retreat in mortgage rates and increased supply, existing home sales dropped to a 7-month low in April, according to the National Association of Realtors.

The average rate on a 30-year mortgage in the U.S. climbed this week to its highest level since mid-February, a setback for home shoppers that threatens to slow sales further this spring homebuying season.

More than 14% of pending home sales in April were canceled. Buyers continue to be hesitant amid the nation's economic uncertainty. Failed sales could be an opportunity for would-be buyers. One in seven pending home sales in the U.S. were canceled in April.

Experts fear that the move, though it could help the government's budget woes, could disrupt the fragile U.S. mortgage market.

Sales of previously owned homes in April declined 0.5% from March to a seasonally adjusted, annualized rate of 4 million units, according to the National Association of Realtors. That is the slowest April pace since 2009. Sales were down 2% from April of last year. Housing economists were expecting a gain of 2.7%.

U.S. existing home sales unexpectedly fell in April despite a temporary drop in mortgage rates and increased supply, and could remain lackluster this year amid rising economic uncertainty.

Growing concern about the national debt impacted home borrowing rates this week. Mortgage rates track the benchmark 10-year Treasury yield, which climbed higher as bonds sold off