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The earliest BTA (SAO RAS 6-m telescope) spectroscopic observations of theGRB 030329 optical transient (OT) are presented, which almost coincide in timewith the "first break" ($t\sim 0.5$ day after the GRB) of the OT light curve.The beginning of spectral changes are seen as early as $\sim 10-12$ hours afterthe GRB. So, the onset of the spectral changes for $t<1$ day indicates that thecontribution from Type Ic supernova (SN) into the OT optical flux can bedetected earlier. The properties of early spectra of GRB 030329/SN 2003dh canbe consistent with a shock moving into a stellar wind formed from the pre-SN.Such a behavior (similar to that near the UV shock breakout in SNe) can beexplained by the existence of a dense matter in the immediate surroundings ofmassive stellar GRB/SN progenitor). The urgency is emphasized of observation ofearly GRB/SN spectra for solving a question that is essential for understandingGRB physical mechanism: {\it Do all} long-duration gamma-ray bursts are causedby (or physically connected to) {\it ordinary} core-collapse supernovae? Ifclear association of normal/ordinary core-collapse SNe (SN Ib/c, and others SNtypes) and GRBs would be revealed in numbers of cases, we may have strongobservational limits for gamma-ray beaming and for real energetics of the GRBsources.Comment: 4 pages, 5 figures. Proceedings of the 4th Workshop "Gamma-Ray Bursts  in the Afterglow Era", Roma, 2004 October 18-22, eds. L. Piro, L. Amati, S.  Covino, and B. Gendre. Il Nuovo Cimento, in pres

The earliest spectroscopy of the GRB 030329 afterglow with 6-m telescope