How do I want to merge the branchA and branchB via Bitbucket API without pull request?

Obviously I can go through the website and do a compare branches or tags to see the differences in branches, from there I can click the merge button to merge the two branches. Am I able to do this via the rest API?

I see this using pullrequests:{projectKey}/repos/{repositorySlug}/pull-requests/{pullRequestId}/merge [POST, GET]

However we do not use pull requests for this so I am looking to just merge branches via the rest API.

Thanks for the help.