Pat, Aug 27: Rebel JD-U leader Sharad Yadav on Sunday pledged to form a ‘Mahagathbandhan’ (Grand Alliance) at the tiol level to defeat and oust the BJP-led NDA in the next general election. “Hindustan bhar mein Gathbandhan banega ab,” Sharad Yadav roared to applause from the large gathering at a rally here organised by RJD chief and former Bihar Chief Minister Lalu Prasad.