The former prime minister wore a fixed grin and stared straight ahead during the awkward encounter.
"Got your big plate, Lee?"
Tory MP had been talking about parts of London and Birmingham amid the Lee Anderson Islamophobia row.
LBC broadcaster and Telegraph columnist warns the Tories that "if you sleep with a dog, you tend to get fleas".
"I'm actually going to effectively put the phone down," host Nick Ferrari said in frustration.
Former leadership candidate Rehman Chishti says the PM has not spoken to him since entering No.10.
MP, who was suspended from the Tory parliamentary party after being accused of Islamophobia, admits only to a "little bit of contrition".
But a government minister said he lost the Tory whip for "anti-Muslim hatred".
The former Tory deputy chairman said it would be "a sign of weakness".
But the deputy PM said yesterday that the former Tory deputy chairman lost the whip because he refused to apologise for his remarks about Sadiq Khan