"Chinese ships have been dispatched to the area. Beijing is expected to make an announcement in a few hours," acting Transport Minister Hishammuddin Hussein told reporters.
One of the objects was very large, measuring 22.5 by 13 metres, the ministry said in a statement, correcting the minister's earlier statistics of 22 by 30 metres.
"This information was received by phone during the press conference, and was initially misheard," the ministry said.
Hishammuddin said earlier: "The news that I just received is that the Chinese ambassador received a satellite image of a floating object in the southern corridor and they will be sending ships to verify."
He said he had no other information and that China would release further details. It was not immediately clear whether the object was seen near where another satellite found two objects earlier this week.
China's Xinhua news agency said the object was about 120 kilometres from the area where Australian satellite images had shown large pieces of debris earlier. Those objects have not been located and could have drifted considerably since they were first sighted, leading to speculation that the Chinese sighting may be the same object.
The development came as frustration grew over the lack of progress tracking down two other objects spotted by satellite earlier in the week.
Nothing has been found in the three days that search crews have been scouring the area where the satellite took images of objects, about 2,500 kilometres southwest of Australia.
Two military planes from China arrived in Perth on Saturday to join Australian, New Zealand and US aircraft in the search. Japanese planes will arrive Sunday and ships were in the area or on their way.
Australian Prime Minister Tony Abbott, on an official visit to Papua New Guinea, said weather hampered the search earlier but conditions were improving.
"There are aircraft and vessels from other nations that are joining this particular search because tenuous though it inevitably is, this is nevertheless the first credible evidence of anything that has happened to Flight MH370," Abbott said.
Hishammuddin said that if the search was unsuccessful, the focus would have to return to two broad arcs where pings from the aircraft, detected by another satellite, may have originated.
Though direct contact with the aircraft was lost early March 8 over the Gulf of Thailand, the pings continued for several hours after that. One arc stretches into central Asia; the other deep in the Indian Ocean.
"My biggest concern is that if we are not able to identify the debris, having to go back to the two corridors is a huge and massive area," Hishammuddin said.
The Boeing 777 disappeared March 8 with 239 people on board less than an hour after taking off from Kuala Lumpur. Hopes that the search could be more narrowly focused grew after a satellite spotted two large objects in the area earlier this week.
One of the objects was 24 metres in length and the other was 5 metres. The objects could be unrelated to the plane; one possibility is that they fell off one of the cargo vessels that travel in the area.
Malaysia has asked the US for undersea surveillance equipment to help in the search, said Rear Adm John Kirby, a Pentagon spokesman.
Some questions had been raised about the cargo of the missing plane because it contained lithium ion batteries. Malaysia Airlines issued a statement saying it was in compliance with the International Civil Aviation Organization and the International Air Transport Association requirements and classified as "non-dangerous goods".
Malaysian authorities have not ruled out any possible explanation for what happened to the jet but have said the evidence so far suggests it was deliberately turned back across Malaysia to the Strait of Malacca, with its communications systems disabled. They are unsure what happened next.
Police are considering the possibilities of hijacking, sabotage, terrorism or issues related to the mental health of the pilots or anyone else on board.