"Iran's efforts to use surrogates to attack Saudi Arabia and destabilize the region needs to be countered," Hook said, as quoted by Al Arabiya broadcaster.
The risk of a regional conflict in the Middle East would rise if Iran was not successfully confronted in Yemen, the envoy added.
According to him, Washington was doing everything possible to defuse tensions with Iran and return the containment system in the region.
However, Hook blamed Tehran for rising tension in the region because of the refusal of any diplomatic initiatives.
"Our diplomacy does not give Iran the right to respond with military force. Iran needs to meet diplomacy with diplomacy, not military force," the envoy added.
Hook is currently on a tour of the countries of the Arabian Peninsula, where he will hold talks with representatives of Saudi Arabia, the United Arab Emirates, Oman, Kuwait and Bahrain about the crisis in the region. In Riyadh, Hook met with Saudi National Security Adviser Musaed bin Mohammed al-Aiban and discussed with him the alleged "threat from Iran."
In the wake of the escalation in the Persian Gulf amid suspected attacks on oil tankers blamed by the US and some of its allies on Iran, the Saudi Arabian foreign minister stated on Thursday that Riyadh does not want a military conflict with Tehran. However, he added that Saudi Arabia was committed to working with its allies to stop what he described as Iran's "aggressive" behaviour. Tehran, in its turn, has strongly denied any involvement in the suspected attacks.
The United States has recently boosted its military presence in the Persian Gulf in what US National Security Adviser John Bolton said was "a clear and unmistakable signal to the Iranian regime that any attack on the interests of the United States or [its] allies will be met with ruthless force."
At the same time, US President Donald Trump has said that he hoped to avoid a war with Iran. Iranian Supreme Leader Ayatollah Ali Khamenei also said that Iran does not intend to wage war with the United States but will continue to resist its pressure.