He clearly placed an arm around Mr Williamson before patting him on the back.
Witnesses say he was heard saying to both parliamentarians: "How are we comrades?"
Although Mr Williamson is suspended by his party, he is still free to take part in wider votes.
He had been in the Commons to vote on an amendment put forward by Mr Corbyn, which eventually failed to pass.
Ian Austin, the MP for Dudley North, who quit Labour last month, told the Mail on Sunday: "If any more proof were needed that the Labour leader couldn't care less about eradicating anti-Jewish prejudice in his Party, this is it."
Labour said Mr Corbyn's actions represented "basic politeness".
