LONDON, March 21 (Reuters) - European shares fell on Monday, as a decline in the share prices of major mining stocks and in French supermarket operator Casino weighed on the region's stock markets.
The pan-European FTSEurofirst 300 index and the euro zone's blue-chip Euro STOXX 50 index were both down by 0.7 percent.
Mining and steel stocks such as ArcelorMittal and Glencore fell as metals prices weakened.
Shares in Casino also fell after Standard & Poor's cut its rating on the company.
However, Bayer's shares rose after people familiar with the matter told Reuters that Monsanto, the world's largest seed producer, had approached Bayer to express interest in its crop science unit, including a potential acquisition worth more than $30 billion. (Reporting by Sudip Kar-Gupta; Editing by Atul Prakash)