Gerry McCann, who was in Liverpool to complete a race in Sefton Park, told Granada Reports: "We feel the authorities, particularly the British authorities, the Metropolitan Police, really want to get to the bottom of it, and because of the leads which are worth investigating, I think is positive."
Madeline McCann vanished during a family holiday in Portugal in May 2007. Her parents have spent the week marking the fifth anniversary of her disappearance.
More top news
Frosty and misty on Sunday night. Quiet and mostly dry into the new week. Risk of frost and fog by night
Quiet and cloudy. Dense fog through Cheshire on Sunday night
Gulf War veteran Paul Briggs' widow, Lindsey, 40, launched legal action to have his life support withdrawn so he could "die with dignity".