"We will face this lawsuit when it comes," the official said, requesting not to be named.
"I have not heard of relatives of Malaysian passengers and crew talking about a lawsuit, but that is their right if they want to sue us," she added.
On Wednesday, a United States firm said it expected to represent relatives of passengers in a lawsuit against Malaysia Airlines and Boeing over the disappearance of the Boeing 777-200 on March 8, according to media reports.
Lead lawyer Monica Kelly from Ribbeck Law said the firm had spoken to family members in many countries and expected about half of them to take part in the suit, Malaysian daily The Star reported.
The jet disappeared from radar about an hour after taking off from Kuala Lumpur en route to Beijing, and is thought to have crashed in the southern Indian Ocean, killing all 239 people on board.
The Chicago-based firm has filed a petition on behalf of Indonesian Januari Siregar, whose son was on the Malaysia Airlines flight, US media reports said.
On Thursday, the Australian body in charge of the search, AMSA, said the search for MH370 had been called off in the area around 2,500 kilometres south-west of Perth, notorious for large waves and strong westerly winds known as the Roaring Forties.
"All planes are returning to Perth & ships are leaving search area," the agency said on its twitter feed.