A United Nations appeal for Yemen Wednesday is aiming at raising $4.27 billion to alleviate what it describes as the world's worst humanitarian crisis, with 161,000 people likely to experience famine there in 2022.

The virtual pledging conference is co-hosted by Sweden and Switzerland. U.N. Secretary-General Antonio Guterres will address donors on the dire needs of the Arab world's poorest country.

Saudi Arabia's octogenarian monarch underwent medical tests had the battery of his pacemaker changed, the state-run Saudi Press Agency reported Wednesday.

King Salman will rest for several days following the procedure and "successful medical tests," the news agency said. Government-produced images showed the king leaving the King Faisal Specialist Hospital in the capital, Riyadh, hunched forward and using a cane, but otherwise walking unassisted.

British Prime Minister Boris Johnson met Wednesday with the de facto rulers of Saudi Arabia and the United Arab Emirates in efforts to ease skyrocketing gasoline prices, as the West grapples with economic headwinds from Russia's invasion of Ukraine.

Johnson was seeking greater investments in the U.K.'s renewable energy transition and ways to secure more oil to lessen British dependence on Russian energy supplies.

Russia has drawn up lists of 40,000 fighters from Syrian army and allied militias to be put on standby for deployment in Ukraine, a war monitor said Tuesday.

Gulf Arab countries are seeking to host rare talks between Yemen's warring parties, including the Iran-backed Huthi rebels, in Riyadh at the end of the month, officials said on Tuesday.

British Prime Minister Boris Johnson is set to visit Saudi Arabia and meet with its crown prince for talks on oil supplies, as he stressed that the West must end its dependence on Russian energy.

Johnson will also use the trip to press Saudi Arabia to condemn Russia's invasion of Ukraine, a Foreign Office official said Tuesday.

At least four people were killed by a car bomb Tuesday in war-torn Yemen. At least eight people, including a senior security official, were injured, officials said.

The explosion took place in the city of Zinjibar and targeted the convoy of Abdel-Latif el-Sayed, commander of the so-called Security Belt force in the southern province of Abyan, the officials said. The casualties were taken to hospitals for treatment, they said.

Israeli forces killed two Palestinians and wounded several others during separate raids in the occupied West Bank, the Palestinian Health Ministry said Tuesday.

Israel's paramilitary Border Police said its forces came under attack while arresting suspected militants.

When Afraa Hashem thinks back about living through the siege of Aleppo, she remembers how inventive everyone was.

In late 2016, Syrian government forces had sealed off Aleppo's rebel-held eastern half, with 270,000 people inside, and for months they and Russian warplanes blasted it to rubble. Food was scarce. Hashem's family, like others, was largely surviving off one meal a day.

Iraq's prime minister met with Kurdish officials on Monday and inspected the site of an Iranian missile attack near the American consulate in the northern Iraqi city of Irbil.

Mustafa al Kadhimi was received by Masrour Barzani, prime minister of the semi-autonomous Kurdish-controlled region. The Iraqi premier also inspected damage caused by some 12 ballistic missiles that landed near the U.S. consulate, which is new and unoccupied, and caused damage to a nearby local television channel.