Malaysia's government said Tuesday that a piece of debris found on Thailand's southern coast was not from missing Malaysia Airlines flight MH370.
The announcement appeared to end speculation about a link to the doomed aircraft, coming a day after Japanese firm Mitsubishi Heavy Industries said the metal panel was probably from a rocket it manufactured.
Malaysia's transport ministry said a team of experts from the government and Malaysia Airlines had examined the debris in Thailand.
"From their detailed report, they have ascertained that the part assembly number, wire bundle number and bolts part number do not match those of a Boeing 777," a transport ministry statement said.
Saturday's find of the debris stirred speculation it may be part of MH370, a Boeing 777 that vanished on March 8, 2014 with 239 people on board en route from Kuala Lumpur to Beijing.
Investigators believe the plane went down in a remote part of the Indian Ocean, though the cause of the disappearance remains a mystery.
Last July a two-metre-long wing part known as a flaperon washed up on a beach on the French-held Indian Ocean island of Reunion, thousands of kilometres from Thailand.
French authorities subsequently confirmed it was from MH370.
Nothing further has been found despite an extensive Indian Ocean search.
On Monday Mitsubishi Heavy Industries said images of the debris found in the Gulf of Thailand featured serial numbers indicating it may be from a rocket it made for launching satellites.