KUALA LUMPUR, March 16 — Malaysia has appealed for help and international coordination in a search for its missing passenger jet stretching across two corridors from the Caspian Sea to the southern Indian Ocean, diplomats said today.

Malaysian officials briefed envoys from about 20 countries on progress in the investigation after calling off a search in the South China Sea for the jet that vanished from radar screens more than a week ago, with 239 people on board.

Although countries have been coordinating individually, the broad formal request marks a new diplomatic phase in an operation expanding across two hemispheres and overshadowed by mounting Chinese criticism of Malaysian-led search efforts.

“The meeting was for us to know exactly what is happening and what sort of help they need. It is more for them to tell us, ‘please put in all your resources’,” T.S. Tirumurti, India’s high commissioner to Malaysia, told Reuters.

The diplomatic initiative could become significant as nations ponder whether to share any military data on the Boeing 777’s fate and fills a void left by the failure of Southeast Asian nations to work as a bloc on the crisis, one diplomat said.

“There are clearly limits to military data but there is an awareness this is a commercial matter,” the diplomat added. — Reuters