Andy Street welcomed the ban on mixing households – enforced in Sandwell, Solihull, Birmingham and soon to be in Wolverhampton.
But he stressed everyone in the Black Country should play their part in tackling the pandemic – amid a surge of cases in the area.
Mr Street said: "This demonstrates very clearly why every citizen across the region must keep doing their bit to keep up the fight against this virus.
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"That’s the only way we can beat it and the only way we can ensure that our children can keep going to school, and people across the region can keep returning to work.
"We are in a critical period. So let’s keep thinking about the education of our region’s children, let’s keep thinking about the people whose livelihoods are under threat, let’s keep thinking about the safety of our loved ones and let’s keep doing the right thing."