Somalia's government said on Monday between 200 and 300 Somalis may have drowned in the Mediterranean Sea while trying to cross illegally to Europe, based on information it has gathered in the past two days from the Somali diaspora and its embassy in Egypt.

“We have no fixed number but it is between 200 and 300 Somalis,” Somali Information Minister Mohamed Abdi Hayir told Reuters by telephone when asked about possible Somali deaths in an incident first disclosed by the Italian president.

“There is no clear number since they are not travelling legally.” The minister said he understood a boat may have been carrying about 500 people, of which 200 to 300 were Somalis “and most of them had died”. He did not give a precise timing for the incident.

One year ago, an estimated 800 migrants drowned off the Libyan coast when the fishing boat they were travelling in collided with a mercantile vessel that was attempting to rescue them - the most deadly Mediterranean shipwreck in decades.

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Egyptian, Italian and Greek officials had earlier been unable to confirm the report of a new sinking.

A UN refugee agency official told Swiss broadcaster SRF he knew of 40 survivors from what appeared to be the same incident.

“We know there are 40 survivors and that as many as 460 people may have been on the boat who sailed from Egypt,” the UNHCR's Beat Schuler told the broadcaster in what it said was a report from Malta.

In an article on the Somali National News Agency (SONNA) website, President Hassan Sheikh Mohamoud on Monday “sent his heartfelt condolence on his behalf and on behalf of the citizens of Somalia to the families who lost their loved ones”.

The president urged Somalis to stand together in helping “stop such hazardous trips to overseas”. Somalia has a large diaspora, with many Somalis in Europe and the United States, after fleeing two decades of conflict.