The Metropolitan Police has 11 weeks to find missing Madeleine McCann before its funds run out. Madeleine vanished from her bed in a holiday apartment in Praia da Luz, Portugal, on the evening of 3 May 2007.
In April, the Home Office gave police an additional £85,000 (€111,000) grant to continue the £12m investigation code-named Operation Grange. The funding will run out in September.
Investigators denied claims the search had reached a stalemate following reports only two trips to Portugal have been made in the past year.
Detectives, who said they do not have to be in Portugal to conduct their investigation, added they are in possession of significant material gathered during previous trips.
"A lot of potentially significant images and material were captured on previous trips to Portugal and we are still working on all leads,"a Met Police spokesperson told The Sun.
"We have spent less on flights and hotel accommodation because we haven't needed to be in Luz to carry on our work. If there are policing reasons we need to be there we will." the spokesperson continued.
Authorities are following a lead that suggests burglars were involved in the disappearance.
A source close to Madeleine's parents said the couple was grateful the investigation was still ongoing.
"It is heart-breaking for Kate and Gerry to still not know after a decade what happened to Madeleine. But to know there is still an active police investigation doing their very best to help find her gives them a strength and comfort," the source said.
"It buoys them up and gives them hope particularly at a time when they have lost a long and bitter court battle against former Portuguese police officer Goncalo Amaral who is free to continue making ludicrous and hurtful claims about Madeleine's disappearance."
Neither police in the UK nor in Portugal have been able to ascertain whether the girl, who was aged three when she went missing, is dead or alive.
Speaking before the 10-year anniversary since Madeleine's disappearance in, Met Police Assistant Commissioner Mark Rowley said in May: "We don't have evidence telling us if Madeleine is alive or dead. It is a missing person's inquiry but as a team we are realistic about what we might be dealing with – especially as months turn to years.
He added the investigation was still significant and the "image of Madeleine remains instantly recognisable in many countries across the world".