Air France has said it will pay a first advance of $24,400 in compensation, through its insurers, to the families of the victims of the June 1 crash in which 228 people died, the company's chief executive has said.

Brazilian and French ships are still searching the ocean for debris and bodies from Flight AF 447 from Rio de Janeiro to Paris which crashed into the Atlantic after flying into stormy weather.

Pierre-Henri Gourgeon, Air France's CEO, said: "The lawyers of our insurers in every country are talking to the victims' families to try and organise this advance payment."

Investigators are still trying to establish the cause of the crash and Gourgeon stressed the payments were a compassionate gesture from the airline, not an admission of liability.

'First batch'

Pierre-Jean Vandoorne, an ambassador appointed by the French government to liaise with the families of victims of the crash, told reporters the payments were "a first batch of aid".

"If I'm correctly informed, it is the insurance company AXA which is in charge of relations between Air France and the families of the victims on this particular aspect of the consequences of the accident," he said.

Asked whether accepting the money would mean that relatives would forfeit their right to sue Air France later, Vandoorne said: "As far as I am aware this [compensation] will not represent an obstacle to any civil suits."

Responding to a question about whether the Air France insurance contract meant that families would receive compensation of approximately $140,000 per victim, he said: "Yes, it's roughly in that ballpark."

Both officials remained very cautious when asked how the probe into the causes of the disaster was going.

Gourgeon echoed French investigators who said this week they were getting closer to understanding what happened but had no certainties yet.

They said they did not know yet whether unreliable speed readings from the plane's sensors had contributed to the crash.

Gourgeon said he had not lost hope that the aircraft's flight data recorders or "black boxes" would be found.

No identification

Passengers from 32 nationalities died in the crash of the Airbus 330, among them 61 French people and 58 Brazilians. 

Vandoorne, who has just returned from a trip to Brazil to liaise with Brazilian authorities involved in the search operations and the autopsies, said 51 bodies had been recovered to date but none had been conclusively identified.

"We will of course be informed immediately as soon as there are certainties but for now we have received no information concerning the identification of any of the bodies that have undergone autopsies," he said.

Vandoorne said the government was informing the families of every new development via letters, email and telephone.

He said: "The families prefer the telephone. What we are noticing is that these stricken families need to talk.

"To at least have someone to talk to, and from whom to get information, is an important element which helps start the mourning process."