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The former Conservative MP admitted both charges earlier in the year, following the collapse of his libel case against The Guardian and World in Action.

Mr Justice Scott Baker sentenced him to 18 months in prison for each offence, with the two terms running concurrently.

The judge told Aitken he had spun a "web of deceit" from which he had not been prepared to escape by telling the truth.

From the dock, the former minister blew a kiss to his family who started to cry as the verdict was announced. He was later taken away to begin his sentence at Belmarsh jail near Woolwich, south London.

Aitken had spoken only briefly during the hearing. Asked to confirm his name was Jonathan William Patrick Aitken, he replied: "It is."

His QC, Sir John Nutting, told the court his client had already suffered enough.

"The fall from grace has been complete, his marriage has broken down, he has lost his home, he is one of only three people this century forced to resign from the Privy Council, he is bankrupt and his health has suffered.

"His public humiliation has been absolute. These are real and considerable punishments."

Sir John said Aitken now felt "profound remorse and shame", particularly for drawing up a false witness statement for his daughter, Victoria, to sign.

The former minister's legal team later said he did not intend to appeal.

The sentence could have been far harsher. Perverting the course of justice carries a maximum sentence of life imprisonment, while perjury can be punished with a seven-year jail term.

Former Foreign Secretary Sir Malcolm Rifkind - who was Aitken's boss when he was defence procurement minister - attended the court to give evidence on Aitken's character.

The prison sentence completes the downfall of a man who previously boasted a £3m fortune and could expect a glittering career in politics or business.

Far from fulfilling his promise to "cut out the cancer of bent and twisted journalism", Aitken's libel action succeeded only in destroying almost every aspect of his life.

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Debt collectors took his Rolex watch and cufflinks, among other possessions from his house last week in an effort to recoup his outstanding £2m legal costs.

Aitken, 56, has declared himself bankrupt and claims to have only £40,000 left in the world.

His £1.5m Westminster home was transferred to his former wife as part of their divorce settlement, although he has continued to live there.

His mother, Lady Aitken, said his fortune has diminished in line with his reputation.

"It's exactly as if he's been imprisoned for the last two years. He's had everything taken away from him. He hasn't been able to make money, had no job."

Aitken pleaded guilty to the charges

In a documentary to be screened on Sunday, Channel 4's The Real Jonathan Aitken, Lady Aitken said despite the scandal that has engulfed her son, she felt "so proud" at how he had coped.

"I think anybody who has had to stick through what he's had to stick through and come through it, really thinking about other people all the time, and not for one minute giving up, is terrific.

"All power to him I say. I'm so proud of him. I'm amazed at his backbone in this.

"He really is too good a man, too good a character to have to suffer all this. I know he has brought some of it on himself. Hopefully, it's just a blip, an awful blip."