Yemen's Houthi rebel movement has issued a warning to the United States and Israel that an attack on Iran - an increasingly likely possibility - could result in a new round of conflict escalation in the region. The group it well-known for its campaign of attacks on shipping, which only subsided after a U.S. air campaign created conditions for a truce earlier this year. That truce may be in danger in the event of a conflict with Iran, the Houthis' primary military sponsor, the group hinted on Wednesday. 

"We are . . . at the highest level of preparedness for any possible American escalation against us," a Houthi source told Newsweek on Wednesday. "Any escalation against the Islamic Republic of Iran is also dangerous and will drag the entire region into the abyss of war. . . . It is certainly not in the interest of the American people to become involved in a new war in service of [Israel]."

Relatedly, the UK Maritime Trade Operations (UKMTO) office of the Royal Navy issued a rare warning to shipping on Wednesday, cautioning operators that it has been made aware of a risk of "an escalation of military activity having a direct impact on mariners." Vessel masters are advised to proceed with caution in the Arabian Gulf, Gulf of Oman and Strait of Hormuz - areas where Iran has previously engaged in attacks on shipping during periods of heightened tension. 

The tensions center on Iran's nuclear program, which Israel views as an existential threat. Renewed U.S.-Iran talks on a new nuclear deal appear stalled, despite initial signs of progress, and President Donald Trump has expressed frustration with the pace of the negotiations. As in previous talks in 2015, Iran is refusing to give up the entirety of its domestic uranium enrichment infrastructure, which the Trump administration insists must be dismantled or relocated to a third country. But the backdrop has changed since the last round of negotiations ten years ago: Tehran now possesses enough high-enriched nuclear fuel that it could produce about 10 nuclear weapons in a "breakout" push, perhaps within a matter of months. 

As the negotiations falter, Israel is widely believed to be preparing for a potential strike on Iranian nuclear sites to pre-empt the manufacturing of an Iranian bomb - and Iran has laid out its plans for a response. Iran's Supreme National Security Council warned on Wednesday that it has "a vast quantity" of intelligence on Israel's nuclear weapons establishment, and is prepared to conduct a counterstrike with its missile forces. Iranian Defence Minister Aziz Nasirzadeh has also threatened to strike U.S. military bases around the region if Iran comes under attack. 

In a sign that hostilities could be imminent, the U.S. government has ordered a heightened state of preparedness for Iranian attacks in the Mideast, to include the evacuation of the U.S. embassy in Baghdad and a voluntary departure authorization for servicemembers' families at bases in the region.