"I did a new mega simple version of 'Heart Of The Country' for the Linda animation on YouTube," McCartney posted on Twitter on Wednesday. The 40-second clip was posted in the United Kingdom on January 11 by "Linda McCartney."

"Sounds cool to me!" he said in Wednesday's tweet. In an earlier post, McCartney tweeted "Looks great - love it!"

In the clip, an animated Linda McCartney snaps photographs, prepares and serves food for children and animals and plays music in a forested setting.

Linda McCartney, who died 15 years ago, was an accomplished photographer and dedicated vegetarian and animal rights activist.

The singer did not say why he re-recorded the song, but people who posted comments on YouTube speculated that the clip and accompanying music would be used for a new advertisement for Linda McCartney's line of vegetarian food products.

Media reports said the ad would air later this month.

"Heart Of The Country" was recorded for Paul and Linda McCartney's 1971 "Ram," which was the only album credited to the pair.

Linda McCartney died of breast cancer in 1998 at age 56.

(Reporting by Chris Michaud; editing by Patricia Reaney and Stacey Joyce)

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