Unless the TD-W8961ND can be configured for repeater mode (highly unlikely), then either you need WDS bridging (which, as as bill001g stated, is very iffy, since WDS is not a wifi standard and incompatibilities across manufacturers is very common), or you need a wireless repeater/extender. More than likely, your TD-W8961ND will only offer a wired option from the primary router to itself configured as an AP.
I suppose another option would be to use a powerline bridge instead of a wired ethernet connection between the devices.
[primary router]<-- wire -->[powerline adapter #1]<-- power lines -->[powerline adapter #2]<-- wire -->[secondary router - ap mode]