The three images, published by the Chinese State Administration for Science, Technology and Industry for National Defence (SASTIND) were taken at 11am on Sunday, March 9, more than 30 hours after the plane was believed to have disappeared.

The pictures, taken by the Gaofen-1 satellite, show what appear to be three large floating objects in the South China Sea, some 226 kilometres from the last recorded transponder signal in the waters northeast of Kuala Lumpur and south of Vietnam.

According to the agency, the pieces measure 13m by 18m, 14m by 19m and 24m by 22m. For context, the missing Boeing 777-200 aircraft is about 64m long.

The agency did not explain why the images were not released until Wednesday. Former US National Transportation Safety Board managing director Peter Goelz told CNN that China may have been reluctant to release the images earlier because "they may not want to reveal what kind of satellite capabilities they have".

While not referring specifically to the images, Chinese Premier Li Keqiang said Chinese authorities were looking "very closely at all suspected clues" shown on all satellite images.

Speaking at the closing press conference of the annual session of the National People's Congress in Beijing on Thursday, Mr Li said China had deployed 10 satellites and eight ships to help with the search. About two-thirds of the 239 on board were Chinese nationals.

"As long as there is a glimmer of hope, we will not stop searching for the plane," he said, adding he had personally spoken to the Chinese captain of one of the search vessels on Wednesday, urging him to "do all he can, and then try harder again".

The latest satellite images are likely to be met with caution after images released early this week of suspected aircraft wreckage in the Gulf of Thailand proved to be wrong.  Since then, the search area has grown from the Gulf of Thailand to include the Straits of Malacca and Andaman Sea west of the Malaysian peninsula.

It is also the latest bit of contradictory information to be released, with Malaysian authorities investigating “radar blips” which indicated the plane had veered sharply off course and had headed west toward the Indian Ocean.

“Today we are still not sure that it is the same aircraft,” Malaysian defence minister Hishammuddin Hussein said of the radar blips. “That is why we are searching in two areas.”

At a hostile press conference military officials said the last possible recording of flight MH370 was at 2.15am on Saturday morning 200 miles north west of Penang. The authorities had initially said air traffic control lost contact at 1.20am on the east side of the peninsula. On Tuesday the head of the armed forces was reported as saying it was picked up by military radar at 2.40am - a statement he has since denied making.

Even with the new Chinese satellite imagery, with so many ships and aircraft combing over the plane’s original flight path, “the Gulf of Thailand is pretty much saturated at this point”, Commander William Marks, spokesman of the US Seventh Fleet, said.

“We’re now going over the same areas.”

Chinese criticism of Malaysian authorities has intensified with an editorial in the state-run Global Times condemning conflicting statements issued by officials in Kuala Lumpur. The piece said the investigation appeared “chaotic” and asked whether Malaysia was deliberately concealing information.

A Chinese foreign ministry delegation sent to Kuala Lumpur held a three-hour meeting with family members of Chinese passenger families who continue to arrive in the Malaysian capital searching for news.

“We will not leave until the aircraft is located,” said Guo Shaochun, the deputy director of consular affairs at the foreign ministry.