Mumbai: The rupee today appreciated a sharp 69 paise, or 1.06 per cent, to trade at an over one-week high of 64.63 against the dollar after the US-based rating agency Moody's upgraded India's sovereign credit rating.

The rally was supported by the dollar selling by exporters and banks and the US unit's weakness against some currencies overseas, traders said.

The key Indian equity indices opened in the green on Friday following global cues.

The 30-scrip Sensitive Index (Sensex) was trading 384.73 points or 1.16 per cent higher during the early session.

The wider 51-scrip Nifty of the National Stock Exchange (NSE) was also trading 118.85 points or 1.16 per cent higher at 10,333.60 points.

US-based Moody's today upgraded India's sovereign credit Rat ng by a notch to 'Baa2' with a stable outlook citing improved growth prospects driven by economic and institutional reforms.

The rating upgrade comes after a gap of 13 years -- Moody's had last upgraded India's rating to 'Baa3' in 2004.

In 2015, the rating outlook was changed to 'positive' from 'stable'.