Dolan, however, echoed comments on Thursday by Malaysian Prime Minister Najib Razak, who said the object was "very likely" from a Boeing 777 but cautioned that it remained to be confirmed, in a case notorious for disappointing false leads.
Dolan said he was hoping for greater clarity within the next 24 hours.
Several experts believe the debris is a Boeing 777 flaperon, a wing part, and that if it is confirmed it almost certainly belonged to the Malaysia Airlines plane, whose disappearance became one of aviation's greatest mysteries.
The debris washed up on the French island of Reunion, some 4000km from the oceanic region where MH370 was thought to have gone down in March last year.
The recovered object is expected to be flown to a testing site in France near the city of Toulouse for analysis by aviation authorities and could reach there by today, French sources told AFP.
Authorities involved in the search at sea, guided by the analysis of signals from the plane that were detected by a satellite, believe it went down in the southern Indian Ocean.
But no confirmed physical evidence has ever been found and Malaysian authorities in January declared that all on board were presumed dead.
Australian Transport and Infrastructure Minister Warren Truss said he remained confident the hunt for MH370 was being conducted in the right area, with wreckage in Reunion consistent with currents from the zone they are scouring.
"It's not positive proof, but the fact that this wreckage was sighted on the northern part of the Reunion Island is consistent with the current movements, it's consistent with what we might expect to happen in these circumstance," he said.
Truss added: "We remain confident that we're searching in the right place."