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The giant HII region W31 hosts the populous star cluster W31-CL and othersprojected on or in the surroundings. The most intriguing object is the stellarcluster SGR1806-20, which appears to be related to a Luminous Blue Variable(LBV) - a luminous supergiant star. We used the deep VVV J-,H-and K$_s$-bandsphotometry combined with 2MASS data in order to address the distance andotherphysical and structural properties of the clusters W31-CL, BDS 113 andSGR1806-20. Field-decontaminated photometry was used to analysecolour-magnitude diagrams and stellar radial density profiles, using proceduresthat our group has developed and employed in previous studies. We concludethatthe clusters W31-CL and BDS113 are located at 4.5kpc and 4.8kpc and have agesof 0.5Myr and 1Myr, respectively. This result, together with the pre-mainsequence (PMS) distribution in the colour-magnitude diagram, characterises themas members of the W31 complex. The present photometry detects the stellarcontent, addressed in previous spectroscopic classifications, in the directionof thecluster SGR1806-20, including the LBV, WRs, and foreground stars. Wederive an age of 10$\pm$4Myr and a distance of d=8.0$\pm$1.95kpc. The clusteris extremely absorbed, with AV= 25mag. Thepresent results indicate thatSGR1806-20 is more distant by a factor 1.8 with respect to the W31 complex, andthus not physically related to it.

VVV analysis of star clusters towards the W31 star-forming complex