The most common and most likely answer to this crossword clue is the 4 letter word FIBS
I've seen this crossword clue in The Daily Telegraph
F
I
B
S
More clues leading to the result FIBS
- Lies first thing in flat, in bed, snoring
- Stories of bimbos regularly exposed
- Untrue accounts from France: irritating affliction
- Lies if coming up with abuse regularly
- Starts to fabricate implausibly bogus stories
- Stories from leaders of famed Indian business society
- If coming around, bachelor lies
- Pork pies in France leading to intestinal discomfort
- FBI troubled by last of Boris’s deceptions
Buddy explains!

The straight part
We know that "Lies" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case lies = fibs.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.
What does FIBS mean?
FIBS noun- A lie, especially one that is more or less inconsequential.
- A liar.
- The fibula.
- A kind of experimental poem where the number of syllables in each line is the next succeeding Fibonacci number.