We study a novel interacting dark energy - dark matter scenario where the anisotropic stress of the large scale inhomogeneities is considered .
The dark energy has a constant barotropic state parameter and the interaction model produces stable perturbations in the large scale of the universe .
The resulting picture has been constrained using different astronomical data in a spatially flat Friedmann-Lemaître-Robertson-Walker ( FLRW ) universe .
We perform different combined analyses of the astronomical data to measure the effects of the anisotropic stress on the strength of the interaction and on other cosmological parameters as well .
The analyses from several combined data show that a non-zero interaction in the dark sector is favored while a non-interaction scenario is still allowed within 68 % confidence-level ( CL ) .
The anisotropic stress measured from the observational data is also found to be small , and its zero value is permitted within the 68 % CL .
The constraints on the dark energy equation of state , w _ { x } , also point toward its ‘ -1 ’ value and hence the resulting picture looks like a non-interacting w _ { x } CDM as well as \Lambda CDM cosmology .
However , from the ratio of the CMB TT spectra , we see that the model has a deviation from the standard \Lambda CDM cosmology which is very hard to detect from the CMB TT spectra only .
Although the deviation is not much significant , but from the present astronomical data , we can not exclude such deviation .
Overall , we find that the model is very close to the \Lambda CDM cosmology .
Perhaps , a more accurate conclusion can be made with the next generation of surveys that are not so far .
We also argue that the current tension on H _ { 0 } might be released for some combinations of the observational data .
In fact , the allowance of w _ { x } in the phantom region is found to be more effective to release the tension on H _ { 0 } .