Image copyright AFP Image caption Benjamin Netanyahu said his son Yair had "no input" in the gas deal involving Kobi Maimon

The son of Israel's prime minister has apologised after an audiotape of him bragging about his father's role in a controversial gas deal was broadcast.

In the tape - said to be from 2015 - Yair Netanyahu, 26, is heard trying to persuade gas tycoon Kobi Maimon's son Ori to lend him money for a stripper.

"Bro, my dad now arranged for you a $20 billion deal and you can't spot [lend] me 400 shekels ($116; £86)?" he asks.

He now says it was "a bad joke" made under the influence of alcohol.

The recording emerged as Israeli police investigate allegations of corruption against Prime Minister Benjamin Netanyahu. He denies any wrongdoing.

Lawyers for the Netanyahu family tried to stop Channel 2 News broadcasting the tape on Monday night, arguing that it was "cheap, vicious gossip" and part of a "witch hunt" against the prime minister. But the TV channel rejected the request.

The recording was reportedly made two-and-a-half years ago while Yair Netanyahu was travelling through Tel Aviv in a government-supplied armoured car with Ori Maimon, another friend, a government-funded bodyguard and a driver.

The friends are heard talking in Hebrew about strippers and how much money they have spent.

Yair Netanyahu complains that Ori Maimon will not lend him money to pay for a stripper even though his father - a shareholder in the oil and gas company Isramco Negev 2 - benefitted from a deal to exploit Israel's offshore Tamar gas field.

"Bro, you have to spot me. My dad made an awesome deal for your dad, bro. He fought, fought in the Knesset [Israeli parliament] for this, bro," he says.

After the tape was broadcast, Yair Netanyahu issued a statement complaining it had been obtained illegally but apologising for his remarks.

"The things I said about Ori Maimon were nothing but a bad joke aimed at mocking him, and any sane person understands that," he said. "I have never taken interest in the gas deal, nor have any understanding of its details."

He stressed that it was a "late night conversation, under the influence of alcohol", and that his words "do not represent who I am, the values I was raised on".

Benjamin Netanyahu's office insisted he had "no connection" to Kobi Maimon and knew nothing of the relationship between their sons.

"Yair had no input into the gas arrangement, and if he commented on the matter, he did so jokingly," it added.