How to connect SFTP using a ppk file

Dear Experts,

I am using Rclone with SFTP from a while with username-passwords.
Now I have a need to connect SFTP using ppk file given -
The ppk file has content in below format :

PuTTY-User-Key-File-2: ssh-rsa
Encryption: none
Comment: amer\abc.xyz@61XN6G3-PC
Public-Lines: 9
AA....
...........
...........
...........
...........
...........
...........
...........k=
Private-Lines: 21
A.....
.
.
.
.
.........ag==
Private-MAC: 55bddd87hfdhre656546ghfghgf90576a6

I have tried setting this file path to both "key_file" and "pubkey_file" fields of SFTP remote but some how I am getting below error -
"NewFs: couldn't connect SSH: ssh: handshake failed: ssh: unable to authenticate, attempted methods [none publickey], no supported methods remain"

Looks like I am missing something, could you please help me to understand what is missing here?

Note I am able to connect sftp using winscp with this ppk file

Rclone Version : rclone v1.69.1

Thanks,
Mahendra

I think ppk is PuTTY specific format. Convert it to something rclone understands.

As per docs:

Key files should be PEM-encoded private key files. For instance /home/$USER/.ssh/id_rsa. Only unencrypted OpenSSH or PEM encrypted files are supported.