The London Mayor pointedly thanked the staff who stayed and kept a limited number of tube stations open amidst a "day of carnage", according to commuters.
Khan himself had to reschedule a BBC interview after crew members were unable to make it on time to the studio because of the strike action, which he deemed as "unnecessary".
But it did not draw sympathy from Londoners, who scrutinised the Mayor for RMT union's decision after he said no strikes would happen if he was elected.
During his election campaign in February, he had called walkouts a failure.
At the time, he said: "Strikes are ultimately a sign of failure.
"Every day there's a strike it caused huge misery and inconvenience to Londoners.
"As Mayor what I'd do is roll up my sleeves and make sure that I'm talking to everyone who runs public transport to make sure there are zero days of strikes."
Commuters took to social media to show their exasperation after millions experienced a gruelling morning attempting to get taxis and make long walks to work.
Getwestlondon speaks to commuters about the strikes
Meanwhile, others argued as a Labour Mayor, he should be supporting strikes.
One tweeter said: "Support the striking workers! Or was the all that stuff about your bus driver dad just PR?"
Despite his encouragement for unions to "get round the table for the sake of millions affected", discussions came to no conclusion between RMT and London Underground Limited (LUL) .
The 24-hour strike is set to last until 5.59pm, although services may not resume as normal until Tuesday morning.
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