Police used tear gas to dispel 400 would-be 'intruders'
Michel Meriaux admits he knew the asylum seekers were assembling in the camp on Christmas Day, but he says it was not up to him to warn the authorities.
He denies knowing in advance that the group was going to attempt to enter the tunnel.
Police used tear gas to disperse the asylum seekers after they breached security at the tunnel entrance.
'Determined'
Eurotunnel has called for the Sangatte to be closed, saying it is "powerless" to deal with refugees' persistent attempts to cross into the UK.
There have been calls for Mr Meriaux to resign, but he says he is only concerned with what took place inside the camp.
He said staff telephoned him on 25 December to say that camp residents had assembled in two waves - around 150 of them gathering at 9pm and another 400 after midnight.
He said the camp was not a detention centre and residents were free to come and go as they pleased.
Meanwhile, former UK shadow home secretary Ann Widdecombe said Mr Meriaux's position was "untenable".
"These people were in his care. He must have known that they were putting themselves in danger but yet he did nothing," she said.
Mr Meriaux has rejected calls from both the Eurotunnel company and the mayor of Sangatte for the camp to be closed.
He says that the refugees are determined to cross into the UK at any price and the closure of the camp would not disperse would-be migrants from the areas around the tunnel and port departure points.
'Mission impossible'
Mr Meriaux has been defended by the French Red Cross, following his interview on BBC Radio 4's The World At One.
The French Red Cross said in a statement: "The interview was carried out in French - as Mr Meriaux does not speak English - and he has stated categorically that he was misreported, and that he did not know anything about the incident in advance."
But the BBC maintains its report is accurate and Mr Meriaux's interview can be heard on this website.
Mr Meriaux had described Tuesday evening's events as a "publicity stunt," saying that it was "mission impossible" to cross the 34 kilometre-long tunnel on foot.
Trains were stopped for 10 hours after French riot police, aided by British officers, broke up the crowd of asylum seekers, arresting 129 of them and transferring others to Sangatte.
Eurotunnel complains there is little it can do and has condemned the UK and French Governments for their "passive" stance towards the problem.