  Here we present the first optical photometric monitoring results of a sample
of twelve newly discovered blazars from the ICRF - Gaia CRF astrometric link.
The observations were performed from April 2013 until August 2019 using eight
telescopes located in Europe. For a robust test for the brightness and colour
variability, we use Abbe criterion and F-test. Moreover, linear fittings are
performed to investigate the relation in the colour-magnitude variations of the
blazars. Variability was confirmed in the case of 10 sources; two sources,
1429+249 and 1556+335 seem to be possibly variable. Three sources (1034+574,
1722+119, and 1741+597) have displayed large amplitude brightness change of
more than one magnitude. We found that the seven sources displayed
bluer-when-brighter variations, and one source showed redder-when-brighter
variations. We briefly explain the various AGN emission models which can
explain our results.
