The most common and most likely answer to this crossword clue is the 5 plus 5 letter word WHITE HOUSE
I've seen this crossword clue in The Guardian
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More clues leading to the result WHITE HOUSE
- Official residence a bit like Chatsworth ends west of river
- It parallels Number Ten — as its occupants do in today’s solutions
- Welcome here for victor with excited eastern audience
- Perhaps the highest office in the world; how he suits, not quite in a way. Egoistic leader
- Wife slapped English TV doctor that’s known for The West Wing
- I see how hut’s turned into large abode
Buddy explains!
The straight part
We know that "It parallels Number Ten" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case it parallels number ten = white house.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.