WASHINGTON — Diplomatic efforts to resolve the conflict between the United States and Iran have encountered fresh difficulties, with disagreements over the future of the strategically important Strait of Hormuz becoming a central obstacle.

The latest development is creating immediate economic consequences. Oil prices climbed more than 2% on Tuesday, with Brent crude moving above $67 a barrel in the latest market trading as investors reacted to weakening hopes for a deal. Reuters reported that oil prices have risen sharply in recent weeks amid uncertainty surrounding the strait.

The Strait of Hormuz is one of the world's most important energy shipping routes. Any prolonged disruption could affect crude oil supplies moving from the Persian Gulf to international markets.

For Americans, the situation could eventually translate into higher gasoline prices, increased transportation costs and renewed inflation pressure if elevated oil prices persist.

President Donald Trump has been pushing for negotiations that would help reopen the waterway while demanding concessions from Tehran. Reuters reported that the diplomatic standoff has intensified as the two sides remain divided over key terms.

The uncertainty is already affecting financial markets. Investors are closely watching energy prices because a sustained oil-price increase could complicate the Federal Reserve's efforts to manage inflation.

Higher energy costs can affect businesses across the American economy, from airlines and trucking companies to manufacturers and retailers. Consumers could also face higher prices if companies pass increased transportation and production expenses through to customers.

The Strait of Hormuz situation is particularly important because shipping activity has fallen sharply. Reuters reported that traffic through the waterway dropped to only six vessels, compared with a 10-day average of roughly 50 vessels.

The reduced shipping activity highlights the scale of the disruption and the difficulty of restoring normal energy flows while negotiations remain unresolved.

Markets are also watching upcoming U.S. inflation data. A stronger-than-expected inflation reading combined with higher energy prices could influence expectations for the Federal Reserve's next interest-rate decision.

For the White House, the diplomatic challenge now carries both national-security and economic consequences. A prolonged Hormuz crisis could put additional pressure on American consumers while increasing uncertainty for businesses and investors.

The situation remains fluid, and further negotiations could change the outlook quickly.

The latest U.S.-Iran standoff has therefore moved beyond diplomacy, with the Strait of Hormuz crisis increasingly becoming a major issue for American energy costs, inflation and financial markets.