An efficient robust reversible blind watermarking for colour images is proposed which enables the recovery of the original host image upon extraction of the embedded watermark. Blind watermarking technique is applied for watermark extraction which does not require host image for extraction. For embedding, two level DWT is performed. Watermark is embedded in the maximum wavelet coefficients of the selected blocks of LH and HL sub-bands of both levels. Blue component is chosen for watermark embedding. This watermark scheme is robust against various geometric and non-geometric attacks. It is proved experimentally that the PSNR of the watermarked image versus the original image is guaranteed to be above 40dB. Also it is proved that the reversibility is also high. The proposed method achieves imperceptibility, robustness and reversibility. Experimental results and performance comparison with other schemes are presented to demonstrate the validity of the proposed algorithm.