"Yesterday, we rejected a media report in which unnamed officials said that engine data showed the plane had kept flying for hours after last contact," Defense and Acting Transport Minister Hishammuddin Hussein said during a briefing on the search for Malaysia Airlines Flight MH370.
The Boeing 777-200 jetliner has been missing since Saturday after departing for Beijing from Kuala Lumpur, Malaysia.
He reported that Boeing and Rolls Royce, which built the engine, said "the reports were not true."
However, Hishammuddin said, international teams were working to verify "that detailed information, but we have nothing to confirm at the moment," Bernama reported.
After six days of futile searches in the Gulf of Thailand near the plane's original flight path, investigators began investigating theories that the jet flew up to four hours after it lost contact with civilian radar Saturday, the Los Angeles Times reported.
"An additional search area may be opened in the Indian Ocean, and we are consulting with international partners about the appropriate assets to deploy," White House spokesman Jay Carney said during his Thursday media briefing in Washington.
Conflicting reports suggested the aircraft, which carried 227 passengers and 12 crew members, sent "pings" to communications satellites, hinting it was still in the air after it dropped from civilian radar, the Times said.
Hishammuddin said the search field is expanding further east into the South China Sea and further into the Indian Ocean.
"We want nothing more than to find the plane as quickly as possible," Hishammuddin said.
"But the circumstances have forced us to widen our search."
A Pentagon official told ABC News that the destroyer USS Kidd, one of the Navy vessels participating in the search, was heading toward the confluence of the Indian Ocean and the Andaman Sea at the request of Malaysian officials.
Investigators examined contents of two oil slicks found in the South China Sea, 60 nautical miles south of the last known contact with Flight MH370 and don't believe either were from the missing plane, Hishammuddin said.
Because the majority of the passengers are Chinese nationals, Beijing has expressed growing frustration with the lack of progress in the search, the Times said.
"All the countries involved must demand that the Malaysians disclose all the information they have. The information they've released so far is implausible. It has caused a lot of confusion and has led to people looking in the wrong place," Hu Hongjun, a professor of civil aviation at Tianjin University, told the newspaper.
Hishammuddin said 57 ships and 48 aircraft were involved in the search, and 13 countries were participating.