Screening and confirmatory methods for Aflatoxin M1 (AFM1) analysis were optimized and studied regarding the European Decision 2002/657/EC requirements. The recoveries of AFM1 from the spiked samples at levels between 0.025 and 0.075 µg kg-1 were 99.6-110.3 % with obtained precision 10.5-13.4 %, confirming the immunochemical method precision and reliability for intensive surveillance studies. According to the regulatory requirements, for confirmation of the obtained positives from the screening, the reference high-performance liquid chromatographic method was evaluated in reference to the performance criteria. The obtained between-day recovery was in the range 67.2-72.8 %, and the precision range 5.4-9.1 %. 205 positives from the screening were subjected to confirmatory analysis. The comparison of the data obtained from the immunoassay and chromatographic method (R2=0.764) revealed a slight overestimation of the screening method, but no cases of false-negative determinations occurred.