The Cabinet minister said he is “embarrassed” by his remarks after he told undercover Daily Telegraph reporters he could “bring the government down” if it “pushed me too far”.
In a statement later, Mr Cable said he regretted the comments and had no intention of leaving government.
Cable was recorded telling reporters – who were posing as his constituents – that he had been involved in a “big argument” over dealing with the banks.
He said the Lib Dems had been pressing for a “very tough approach” which had been opposed by “our Conservative friends” and said he had been involved in a “big battle” over the cap on non-EU economic migration, writes the BBC.
Asked about his influence in the government, he reportedly said he was prepared to use the “nuclear option” and resign, if he was pushed too hard.
“I have a nuclear option; it’s like fighting a war,” Mr Cable was recorded saying.
“They know I have nuclear weapons, but I don’t have any conventional weapons.
“If they push me too far then I can walk out and bring the government down and they know that.
“So it is a question of how you use that intelligently without getting involved in a war that destroys all of us.
“That is quite a difficult position to be in and I am picking my fights. Some of which you may have seen.”