I am trying to generate public/private key pair using ECDSA curve secp256k1

On generating public key from ec256.pem (private key) the following error is thrown

"Load key "ec256.pem": invalid format"

Commands used to generate private key:

```
openssl ecparam -name secp256k1 -out secp256k1.pem
openssl ecparam -in secp256k1.pem -genkey -noout -out ec256.pem
chmod 400 ec256.pem
```

Command used to generate public key:

```
ssh-keygen -y -f ec256.pem
Below is the error thrown on running the above cmd ,
Load key "ec256.pem": invalid format
```

The version being used are

OpenSSH_7.4p1, OpenSSL 1.0.2k-fips

I need to generate public key in ssh format for ec256.pem private key