Sultan Kosen, who stands at 8ft 3in (2.5m), said he has a lot in common with Chandra Bahadur Dangi, despite the 6ft 6in (2m) difference between them.
Mr Kosen, 31, from Turkey, said: “Even though he is short and I am tall, we have had similar struggles throughout our lives and, when I look into Chandra’s eyes, I can see he’s a good man.”
The difference in height between Mr Kosen and Dangi, who is 21.5in (55cm) tall, is equal to former US basketball player Michael Jordan.
It is also 8in (20.3cm) taller than the average British man, who measures 5ft 10in (1.78m).
Mr Dangi, 75, from Nepal, said: “It’s been a life-long dream to travel and becoming a Guinness World Records title holder has enabled me to do that.
“I’m honoured to be in London; I’ve always wanted to visit and the fact I get to meet Sultan is special. It makes me extremely proud to represent Nepal all around the world. I’m extremely humbled by the support I receive.”
Mr Kosen and Mr Dangi met at St Thomas’ Hospital as part of Guinness World Records Day and the 60th anniversary of Guinness World Records.
Other record attempts that took place today include the farthest basketball shot backwards and the most people eating breakfast in bed.
On Wednesday, hundreds of people gathered near London’s Tower Bridge to break the record of the largest gathering of people dressed as penguins.
A total of 373 people were dressed as the birds. The previous record was 325 participants.