Rising gasoline prices are already starting to bite U.S. household ​finances and Americans overwhelmingly expect fuel costs will keep climbing as Donald Trump’s war with Iran crimps ‌global oil supplies, a new Reuters/Ipsos poll found.

Some 55% of respondents in the Tuesday-through-Thursday poll said their household finances had taken at least “somewhat” of a hit from the increases in gas prices. Among those seeing an impact, 21% said their finances were affected “a great deal.”

The average price of gasoline ​in America has surged by nearly a dollar per gallon since February 28 when the U.S. and Israel ​attacked Iran, prompting Iranian counterstrikes on the energy installations of U.S. allies and the effective closure ⁠by Iran of the Strait of Hormuz, which carries one-fifth of the global oil supply.

The economic risk is so dire ​that the Trump administration has mulled deploying thousands of additional U.S. troops to ensure safe passage of oil tankers through the ​strait, an endeavor some officials have warned might require deploying U.S. troops to Iran’s shoreline.