Reuters) - The parents of Madeleine McCann demanded a review of the case of their missing daughter on Wednesday, saying they were sick of "fluffy, useless words" from government officials.

Kate McCann and her husband Gerry said the British and Portuguese governments were not doing enough to find Madeleine, who was snatched from a holiday apartment in Portugal 3-1/2 years ago when she was three years old.

"The public think our government and the Portuguese are still searching for her," Gerry told The Sun newspaper. "But the truth is that only our private investigators are.

"We feel badly let down. Madeleine is still missing, there is still an abductor out there."

The couple said the Portuguese police effectively stopped searching for Madeleine a few weeks after she disappeared in May 2007 and they took over, drawing on public support to their "Find Madeleine Fund."

This week, they launched an online petition urging the two governments to review the case. The formal inquiry was closed in July 2008.

"I am fed up with fluffy, useless words," Kate McCann told the Sun. "The evidence is spread all over the place -- we have certain pieces, the Portuguese police have certain pieces. But without putting them together we can't do anything."

The McCanns, both 42, said they only have enough money to pay private investigators until next spring.

But they said they would not give up."There is absolutely no evidence that Madeleine has been physically harmed. We must keep looking for her and those who took her," Gerry said. "No parent would ever give up on their child."

A Home Office spokesman said: "The government wants to ensure that everything feasible is being done to progress the search for Madeleine. The British authorities will maintain a dialogue with the Portuguese and continue to liaise with Madeleine's family on any developments."

(Reporting by Anna Yukhananov; Editing by Steve Addison)