This is in MA.

When we purchased our property, we were granted a right-of-way to access our backyard which runs over another property owner's driveway. Said owner is claiming they can park on the driveway and obstruct the right of way so long as they're willing to move their vehicle(s) when requested.

My understand is that a right-of-way cannot be obstructed by any party (owner, grantee or otherwise).

Any insight appreciated.