In a post on his website Jon Lord says:
It all seems like a lot of hot air and wild speculation to me.
I like Lars and what he has achieved with Metallica. He’s obviously always been very complementary in his comments about DP, and I love the story of his famous nine-years-old “baptism of fire” at our ‘73 concert in The KB Halle in Copenhagen, but if I was asked to be involved in a “Mark III” reunion - (which, by the way, I haven’t. All I ever said was that the idea had a few good points and a few not-so-good points.) - and I indeed considered that offer, I would not be able to even imagine it without the presence of Ian Paice.