Chinese families of passengers onboard missing Malaysia Airlines flight MH370 have reacted angrily to an official declaration there are no survivors.

The head of the Malaysia's civil aviation authority made the statement at a press conference on Thursday.

"Thirteen nations have also lost sons and daughters to this tragedy," Azharuddin Abdul Rahman said.

"It is nonetheless important that families try to resume normal lives, or as normal a life as may be possible, after this sudden loss."

But Malaysia's announcement did not go down well with Chinese relatives who still cling to hope their loved ones can be found.

Of the 239 passengers onboard, 154 were Chinese nationals.

"Malaysia has made this announcement without any evidence," said Jiang Hui, whose mother was on board the flight.

"It is cold, cruel, irresponsible and illegal. It takes away our only pillar of support."

Rumours had been circulating that the Malaysian government was about to make the grim announcement.

Sorry, this video has expired Chinese families of MH370 victims angry at Malaysia's announcement ( Huey Fern Tay )

Earlier in the day emotional Chinese relatives gathered near the Malaysian embassy in Beijing chanting slogans such as "return our family members" and "resist all the way" in an attempt to prevent the bad news from being made official.

A team of policemen watched over the group of peaceful demonstrators.

Such gatherings, organised by a family support group, have not always gone smoothly.

A private meeting with the media was disrupted by Chinese police and the ABC was among those questioned.

Distressed Chinese families vowed they would not let the matter rest.

"We are in our sixties. What is there to be afraid of?" Wang Juncai said.

"We are doing this for our children. We have been waiting for 10 months. This announcement is illegal because there is no evidence."

Sorry, this video has expired Chinese police question ABC journalist

Chinese relatives remain deeply suspicious about the plane's disappearance even though Malaysia said there was nothing to substantiate any speculation about why the plane turned around and vanished.

China's foreign affairs ministry offered their condolences.

The search for the missing plane is continuing, as does a safety and criminal investigation.

An interim report will be released by the Malaysian department of civil aviation on March 7, the eve of the anniversary of the plane's disappearance.