West Asia tensions: Is US-Iran heading for their biggest clash? What we know

Tensions are rising across the Middle East as two US aircraft carrier strike groups remain in the region and a third heads there. Iran has stepped up military exercises, while Israel has reportedly conducted sorties near the Iranian border. Security advisories, flight cancellations and the evacuation of Indian pilgrims have added to concerns over another round of strikes against Iran.

Negotiations remain stalled, with the two sides exchanging threats over Iran's refusal to surrender its enriched uranium and open the Strait of Hormuz, which accounts for 20% of global oil trade. Experts have suggested that elections in Israel and the US could influence the timing of any military action.

Israeli Prime Minister Benjamin Netanyahu faces an electoral battle on October 27, while the US midterm elections will determine control of Congress. US President Donald Trump had pledged not to attack Iran before the November 3 elections, but his latest threats have raised concerns that strikes could be imminent. His envoy to Turkiye said America could strike Iran "as soon as this weekend".

Third US aircraft carrier heads to Middle East

The US has dispatched a third aircraft carrier strike group, led by the USS Theodore Roosevelt, to the Middle East. It is accompanied by the USS Makin Island amphibious readiness group and two amphibious landing ships. Together, they are carrying more than 7,000 sailors and 2,000 Marines, AP reported.

By early November, the US is expected to have more than 20,000 sailors and Marines and hundreds of aircraft in the region. The USS George HW Bush and the USS George Washington are already there.

The deployment would give Trump options to intensify attacks on Iran or deploy ground forces to secure the Strait of Hormuz. Some experts, however, believe the additional deployment could be a negotiating tactic.

Trump has also raised the possibility of using the so-called "mother of all bombs" against Iranian energy infrastructure and nuclear sites. The GBU-43/B Massive Ordnance Air Blast, or MOAB, weighs about 9,800 kg and is designed to destroy tunnels, caves and fortified structures.

Iran steps up military exercises

Iran has been conducting military exercises across the country, including the launch of 30 ballistic missiles in one operation, CNN reported. Statements from Tehran indicate that commanders are preparing for a possible resumption of hostilities.

The Islamic Revolutionary Guard Corps, or IRGC, also unveiled what it called a new weapon, the "father of all bombs". "This is something new for the enemy," IRGC spokesperson Hossein Mohabi told local media.

The IRGC has threatened to use new long-range missiles during any escalation. Analysts have suggested that these could reach US airbases in Britain or the Ramstein logistics hub in Germany. Earlier this month, the US moved its long-range bombers stationed in the UK back to their home base.

Mohsen Rezaei, secretary of Iran's National Security Council, said there would be "zero red lines" this time. He said potential targets would include oil facilities, undersea cables, data centres and artificial intelligence facilities across the Gulf.

US issues security advisories

US diplomatic missions across the Middle East have issued fresh security warnings. Embassies in Saudi Arabia, Bahrain, Qatar and the UAE have warned that hostilities could escalate rapidly and without notice.

The advisories urged American citizens to prepare for possible flight cancellations and airspace closures. Attacks by the Iran-backed Houthis in Saudi Arabia have further raised tensions.

On October 21, the US Department of State ordered some diplomats and their family members to leave its missions in Saudi Arabia. It is also considering withdrawing family members from other missions in the region.

India alerts nationals amid flight cancellations

India has asked its nationals in Saudi Arabia to take "due precautions" and warned them about possible aerial attacks. The advisory followed a Houthi missile strike on Riyadh's King Khalid International Airport that killed an Indian national and injured several others.

Indian airlines have cancelled flights to Saudi Arabia until October 31, while some have extended cancellations until November 30. Around 4,000 Indian pilgrims stranded in Mecca and Medina are being evacuated.

Israeli jets conduct sorties near Iran

Dozens of Israeli fighter jets conducted sorties close to the Iranian border earlier this week, Axios reported. The sorties coincided with a secret meeting between US Defence Secretary Pete Hegseth and Netanyahu.

The exercise involved fighter jets and refuelling aircraft following a flight path consistent with a potential strike on Iran through Syrian and Iraqi airspace. Israel described it as a training exercise intended for "power projection".

US sources said Israel might have sought to provoke Iran into firing at its aircraft, potentially providing a justification for strikes. The deployments, exercises, advisories, cancellations and sorties together signal rising tensions as negotiations remain stalled.