Brent crude futures climbed to roughly $91 a barrel on Monday after Iranian media said an oil tanker had been seized in the Strait of Hormuz, a key global oil shipping chokepoint. Markets were also weighing President Trump's threat to bomb Oman if the country "gets in the way" of U.S. efforts to reach a peace deal with Iran. The move came as Iran adopted a harder line in recent weeks, striking several tankers trying to pass through the strait. Bonds also weakened, sending the 30-year Treasury yield to a fresh 19-year high of 5.31%, while the 10-year yield edged up to 4.725% from 4.695% on Friday.