South Yorkshire Police said officers formally ended their search on Kos on Sunday afternoon, and a full update will be released from the team on the island at midday today UK.
Ben, from Sheffield, disappeared on July 24 1991, aged 21 months, after travelling to the island with his mother and grandparents.
Kerry Needham told the Daily Mirror she is “still in limbo”, adding: “They know he’s dead but just can’t find him. Police said it’s time we ended our 25-year search. They are right but I can’t say goodbye knowing he’s still on that island somewhere. I feel physically sick. I can’t feel any worse than I do.
“He didn’t leave Kos, he didn’t walk away ... Somebody didn’t take him, so he’s here somewhere. They believe he is there but they can’t dig in everyone’s gardens or homes that have been built over the years. I want to tear up the whole island to find him.
“Someone knows where he is. For God’s sake, help me find him. We know he’s dead but we need to find him. When someone dies you find a special place.”
The search operation was prompted by information that digger driver Konstantinos Barkas, also known as Dino, may have been responsible for the toddler’s death, as he was clearing land with an excavator near where Ben was playing on the day he vanished.
Mr Barkas is believed to have died from stomach cancer last year.
After a search lasting three weeks, South Yorkshire Police said on Sunday: “The physical search of two sites on Kos, Greece, has formally come to an end.
“Work continues behind the scenes as officers begin to process the findings from each site.”
Two weeks into the search, detectives said they had accumulated more than 60 items of interest that they will bring back to the UK for forensic testing.
A variety of theories on his fate and reported sightings have arisen since Ben’s disappearance, and Ms Needham had been hoping that she would one day be reunited with her son.
Earlier this year, South Yorkshire Police received extra funding from the Home Office to help in the search for Ben.
Ms Needham has been forthright in her support of the investigation.