Heidi and Spencer, dubbed Speidi, have been taking in all the landmark sights before their rumoured appearance on this year's Celebrity Big Brother, which kicks off tomorrow (3 January).
After a busy day in London, Heidi told her fans about their travels and admitted that Spencer's new phone had been lost somewhere along the way.
"Another wild NYE! So wild Spencer can't find the new phone I got him for Christmas," she said.
"It's probably in the hotel, but since we've been here, we've seen Big Ben, London Bridge, Buckingham Palace, went ice skating, and played in red phone booths and taxis."
Heidi then made the common tourist mistake by thinking London equates to the entire country...
"Basically, he could've lost it anywhere in the UK," she added.
Heidi and Spencer, who have been married for four years, have kept a low profile and not tweeted any pictures of their trip, adding to the CBB rumours.
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