Saudi Arabia, a supporter of rebels fighting to topple President Bashar al-Assad, has raised its level of military alertness in anticipation of a possible Western strike in Syria, sources familiar with the matter said on Friday.
The United States has been calling for punitive action against Assad's government for a suspected poison gas attack on a Damascus suburb on Aug. 21 that killed hundreds of people.
Saudi Arabia's defense readiness has been raised to "two" from "five," a Saudi military source who declined to be named told Reuters. "One" is the highest level of alert.
"It is a must, no one knows what will happen," he said.
The source said other countries in the region, including Jordan, Turkey and Israel, appeared also to have raised their level of military readiness.
A second source said Saudi Arabia's defense readiness had been raised last week, and meant that all leave for the armed forces would be cancelled.
The sources declined to give further details of what a change in alert level would mean, but analysts said it was likely some forces would be moved closer to national borders.
In Kuwait lawmakers have asked their government to inform them about plans for readiness to deal with repercussions of a strike on Syria, Kuwaiti newspapers reported.
The prime minister, Sheikh Jaber al-Mubarak al-Sabah, held an extraordinary cabinet meeting on Thursday, al-Watan reported.
Interior minister Sheikh Mohammad al-Hamad al-Sabah was told to take all necessary measures in case of an emergency that might arise as a result of strikes, the paper said.
Saudi Arabia, a major U.S. ally, Qatar and other Sunni Muslim powers back the mainly Sunni rebels battling Assad, who is from Syria's minority Alawite sect, an offshoot of Shi'ite Islam. The rebels have been joined by foreign Sunni jihadis.
Assad enjoys military support from Iran, Lebanon's Hezbollah and among Iraqi Shi'ites.