A member of the European Central Bank's Governing Council indicated on Friday that the ECB could raise interest rates again as early as next month if signs emerge that inflation in the eurozone is spreading beyond the energy sector, even as a U.S.-Iran agreement has put downward pressure on oil prices.

The ECB implemented its first interest rate hike in three years last week. Subsequently, a provisional peace agreement reached between the United States and Iran triggered a significant drop in oil prices, easing concerns about persistent inflationary shocks driven by energy costs.

Pierre Wunsch, the Governor of Belgium's National Bank and a member of the ECB's Governing Council who is often viewed as a policy hawk supportive of higher rates, stated that a confirmed agreement should lower inflation and support economic growth in the eurozone—potentially even leading to an oil supply surplus next year.

However, he argued that the ECB might still need to raise rates again if inflation in sectors like services continues to rise, even if it might later necessitate cutting rates again.

"The inflation data we are seeing for services is not very encouraging," Wunsch said, referring to the rise in eurozone services inflation from 3.0% to 3.5% in May.

"If this persists, for safety's sake, perhaps we should raise rates by another 25 basis points, then wait and cut rates when the inflationary trend begins to reverse."

The ECB's current deposit rate stands at 2.25%. Market expectations are for the bank to implement another 25-basis-point hike in either September or October, with a further possible increase early next year.

Following last week's ECB rate hike, sources indicated that policymakers saw a greater chance of a rate increase in September than in July, barring a rebound in oil prices.

Wunsch stated he would only support waiting until September for a rate hike if upcoming data remains inconclusive. He emphasized the need to monitor inflation in sectors not directly linked to energy, as well as wage developments.

"If the data is not moving in the right direction, I would call for a second rate hike rather than waiting," he said.

"But if what we are seeing is still unclear, I don't think there is a need to rush."

Wunsch acknowledged that, given the Iran agreement is in place and wage growth has slowed, some might argue the ECB could have forgone a hike last week and temporarily ignored the inflation spike driven by energy prices.

He mentioned that last week he even warned colleagues about the potential for an oil supply surplus within a year, with crude prices possibly falling below pre-Iran conflict levels.

Nevertheless, he stood by the ECB's decision, noting it was made during a period of rising inflation and heightened uncertainty.

"Did we make a mistake? No," he said. "We raised rates by 25 basis points amid rising inflation, so real interest rates actually declined slightly. If necessary, we can cut rates at some point," he added.