Five teams from around the world will soon be competing
Giant blocks of ice have been imported to central London for the city's first ice sculpting festival.
Artists will spend two days sawing and chiselling the two-ton blocks into sculptures in the contest outside the Natural History Museum.
Global entrants will create pieces on the theme "wildlife in the city".
UK artists Nick Fox, from Derbyshire, and Natalie Staniforth, from Surrey, will sculpt a giant "Godzilla-style pigeon trampling poor London".
"It includes Big Ben, the Gherkin and we're hoping to include part of the London Eye," said Mr Fox.
The blocks of ice were imported from Belgium for the competition, which also features artists from France, Italy, the Netherlands and Bulgaria.
Organiser Carol Cordrey said they would create sculptures of ants, trees and penguins, among other subjects.
She had the idea when she saw a snow sculpting competition on holiday in Switzerland.
"I thought how wonderful it would look in London, how exciting to encourage people to come and enjoy it," she added.
Ms Staniforth said it was relatively easy to sculpt in ice as it was much softer than stone.
But despite the cold weather, she said London's relatively mild climate presented difficulties.
"Normally when you work with ice, you can put pieces on. It's too warm for us to attach other pieces today," she said.
The winner will be announced at 1100 GMT on Sunday.