Petra Ecclestone's Ex-Husband Pissed She Wanted to Change Kids' Last Name

Petra Ecclestone has withdrawn her request to change her kid's last name to hers and drop that of her ex-husband James Stunt ... but not before some angry filings from Stunt.

In Stunt's opposition docs, obtained by TMZ, he opposed the billionaire heiress' request in their bitter divorce to change their children's surnames from Stunt to Ecclestone.

In the docs, James argued it would not be in the kids' best interests to drop their father's name and replace it with their mother's ... claiming it would alienate him from his offspring.

What's more, James says he's concerned the Ecclestone name has been tarnished and could lead to danger for the kids ... pointing to reports their famous grandfather, Formula 1 racing honcho Bernie Ecclestone, recently defended Vladimir Putin as "honorable."

Clearly, for some reason, Petra had a change of heart, because she's dropped the request altogether ... but there's still a chance she could refile.

TMZ broke the story ... Petra filed legal docs trying to change their kids' names, claiming he's an "absentee father who is subject to regular negative media and tabloid articles and criminal investigation."

In his opposition, James says he recently found out Petra was already using Ecclestone for the kids without his permission, and before a court ruling ... claiming Petra recently displayed their daughter's name as Lavinia Ecclestone, instead of Lavinia Stunt, on birthday party flyers.