I can't. If I tell the truth that means Frosty has to melt.
7 seconds sound clip from the Rudolph and Frosty: Christmas in July movie soundboard.
You can hear this line at 01:23:45 in the Blu-ray version of the movie.
Quote context
[...]
- Parting brings sorrow, but maybe tomorrow with luck we'll meet again.
- And that's the whole story, Big Ben.
- Rudolph, you gotta get your nose back.
- I can't. If I tell the truth that means Frosty has to melt.
- Not necessarily. No time to explain. I gotta swim like thunder.
- The poor frozen fool gave me his hat when I promised to return your nose.
[...]