Prime Minister Najib Razak said with new satellite data authorities have "concluded that MH370 flew along the southern corridor and that its last position was in the middle of the Indian Ocean west of Perth. This is a remote location, far from any possible landing sites," he told a press conference Monday in Kuala Lumpur.

"It is therefore with deep sadness and regret that I must inform you that according to this new data flight MH370 ended in the southern Indian Ocean.”

He said the new information was based on unprecedented analysis of data from British satellite telecommunications company, Inmarsat.

Najib said more details about this discovery will be presented on Tuesday.

"We share this information out of a commitment of openness and respect to the families," he said, "Two principles that have guided this investigation."

He said Malaysia Airlines has "already spoken to the family of passengers and crew. For them the past few weeks have been heartbreaking." Najib urged the media to "respect their privacy and allow them the space they need at this very difficult time."

The information was sent to the families via a text message that said, "we have to assume beyond any reasonable doubt that MH370 has been lost and that none of those on board survived."

Malaysia Airlines said that the text message was used "only as an additional means of communicating with the families."

The Boeing 777 disappeared from civilian radar on March 8 en route from Kuala Lumpur to Beijing with 239 people on board.

No confirmed sighting of the plane has been made since, but several pieces of unidentified debris have been spotted about 2,500 kilometers (1,550 miles) southwest of Perth, where authorities say the plane went down.

hc/ph (Reuters, AFP, AP, dpa)