By Tamiyuki Kihara, Tim Kelly and John Geddie

TOKYO, March 18 (Reuters) - Japanese Prime Minister Sanae Takaichi visits the White House on Thursday for meetings that offer U.S. President Donald Trump a chance to lean on a key security partner for support in his Iran war, threatening to strain a decades-old alliance.

Takaichi is the first major ally set for face-to-face talks with Trump since he demanded that Japan, among a coalition of nations, send ships to escort tankers through the Strait of Hormuz waterway, largely closed by Iran in the conflict.

BEIRUT, March 18 (Reuters) - An Israeli airstrike hit Beirut's Bachoura neighbourhood in the centre of the city on Wednesday, a Reuters witness said, with a loud explosion heard in the area after the Israeli military warned residents to evacuate a building ahead of the strike.

The attack was part of a broader wave of Israeli strikes on Lebanon on Wednesday, including raids on other parts of the Lebanese capital, as well as southern and eastern areas of the country, signalling an intensification of Israel's campaign against the Iran-backed Hezbollah.

March 18 (Reuters) - Global air travel remains severely disrupted after the war in Iran forced the closure of key Middle Eastern hubs including Dubai, Doha and Abu Dhabi, stranding tens of thousands of passengers.

Below is the latest on flights, in alphabetical order:

AEGEAN AIRLINES

Greece's largest carrier cancelled flights to Tel Aviv, Beirut and Amman until April 22, and to Erbil and Baghdad until May 24. Flights to Dubai were cancelled until April 19 and to Riyadh until April 18.

AIR BALTIC

By Tim Kelly

TOKYO, March 18 (Reuters) - U.S. President Donald Trump's call for allies to send warships to escort oil tankers through the Strait of Hormuz has revived questions about how far pacifist Japan can go to support its closest ally in a conflict.

Here are the narrow legal options available to Prime Minister Sanae Takaichi and the past precedents that could shape her decision.

POLICING ROLE

After its defeat in World War Two, Japan adopted a U.S.-drafted constitution that renounced the use of force to settle international disputes.

By Ahmed Rasheed and Yomna Ehab

BAGHDAD, March 17 (Reuters) - The Iraqi government and the Kurdistan Regional Government reached an agreement to resume oil exports to Turkey's Ceyhan energy hub starting on Wednesday, Iraq's oil minister said on Tuesday.

Oil flow from Ceyhan port is expected to start at 10 a.m. local time (0700 GMT) on Wednesday, state media said, citing Iraqi Oil Minister Hayan Abdel-Ghani.

The UN nuclear watchdog said Wednesday that Iranian authorities had reported projectile impact at the country's only operational nuclear power plant that caused no damage.

The International Atomic Energy Agency (IAEA) "has been informed by Iran that a projectile hit the premises of the Bushehr NPP on Tuesday evening", the Vienna-based agency posted on social media. "No damage to the plant or injuries to staff reported."

Agency head Rafael Grossi "reiterates his call for restraint during the conflict to avoid any risk of a nuclear accident", the statement said.

SYDNEY, March 18 (Reuters) - Australian Prime Minister Anthony Albanese said an Iranian projectile on Wednesday hit near its Al Minhad Air Base in the United Arab Emirates, and that all Australian defence personnel were safe.

"There was minor damage to an accommodation block and a medical facility due to a small fire that was created as a result of that projectile hitting on a road leading up to that base," Albanese told reporters in Tasmania.

(Reporting by Renju Jose in Sydney; Editing by Himani Sarkar)

Having failed to clearly define an objective or exit strategy -- and sell the American public on a new war in Iran -- President Donald Trump finds himself at an impasse, mere weeks into the conflict.

Add to that the high-profile protest resignation of a senior US counterterrorism official on Tuesday, who said publicly that the Islamic republic posed "no imminent threat to our nation" and he couldn't "in good conscience support the ongoing war in Iran."

March 18 (Reuters) - A drone attack targeted the U.S. embassy in Baghdad and an explosion was heard in the area, security sources said early on Wednesday.

(Reporting by Ahmed Rasheed; Editing by Tom Hogue)

Israel repeatedly struck central Beirut on Wednesday, with Lebanese authorities reporting a death toll of at least 12 including a director for Hezbollah's Al Manar TV channel, and began striking river crossings in south Lebanon.

Lebanon was drawn into the Middle East war on March 2 when militant group Hezbollah launched rockets towards Israel to avenge the killing of Iran's supreme leader Ayatollah Ali Khamenei.