EMR Serverless Read From S3 Cross Account - amazon-web-services

Question

I have an EMR Application that runs inside a VPC in a Private Subnet with NAT on.
This application can read files from the buckets in the same account, but when it tries to read a file in a bucket in other aws account it gets access denied.
The emr applications has the following policy:
S3FullAccess:
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": [
"s3:*",
"s3-object-lambda:*"
],
"Resource": "*"
}
]
}
EMR Spark packages settings:
--conf spark.jars.packages=org.apache.hadoop:hadoop-aws:3.2.0
Job Spark:
from pyspark.sql import SparkSession
spark = (SparkSession.builder
.config("spark.hadoop.fs.s3a.fast.upload", True)
.config("spark.hadoop.fs.s3a.impl", "org.apache.hadoop.fs.s3a.S3AFileSystem")
.config("spark.sql.adaptive.enabled", "true")
.config("spark.jars.packages", "org.apache.hadoop:hadoop-aws:3.2.0")
.enableHiveSupport().getOrCreate()
)
df_from_another_s3_account_bucket = spark.read.parquet('s3a://bucket_account_b/path/file.parquet')
This execution is returning the error:
java.nio.file.AccessDeniedException: s3a://bucket_account_b/path/file.parquet: getFileStatus on s3a://bucket_account_b/path/file.parquet: com.amazonaws.services.s3.model.AmazonS3Exception: Forbidden (Service: Amazon S3; Status Code: 403; Error Code: 403 Forbidden;
I have tried using credentials in the spark configs:
.config("fs.s3a.access.key", key_bucket_account_b)
.config("fs.s3a.secret.key", secret_bucket_account_b)
I have also tried creating a bucket policy allowing the emr aws account, but still got the same error.
{
"Version": "2012-10-17",
"Id": "Policy1543283",
"Statement": [
{
"Sid": "Stmt1412820423",
"Effect": "Allow",
"Principal": {
"AWS": "arn:aws:iam::emr_aws_account:root"
},
"Action": "s3:*",
"Resource": "arn:aws:s3:::bucket_account_b"
}
]
}
What else could I try?