The Labour peer at the heart of the Lords sleaze row has secret links to Soviet Russia, a Mail on Sunday investigation has uncovered.

The party faced calls for a new inquiry into Lord Truscott in the face of fresh information about his astonishing rise to power, which throws new light on the 'love at first sight' account of how he met his Russian wife Svetlana in the former Soviet Union.

At the time they married, Lady Truscott was an active member of the Communist Party and her father was a senior Red Army officer at a secret military institute connected to the Soviet equivalent of the SAS.

The Mail on Sunday has also obtained new details about the couple's private fortune, which includes a £1million home in Mayfair, a country home in Bath and property interests in Russia.

Meanwhile, Lord Truscott faces new questions about his political career, and the way he has used it to promote and defend Russian leader Vladimir Putin and the country in general.

This newspaper has been told that Lord Truscott was awarded his peerage by Tony Blair in 2004 after offering private advice on relations with Russia.

He chose a double-headed eagle identical to Russia's official emblem for his heraldic crest as Baron Truscott of St James, then joined Labour's defence team in the Lords before becoming a Minister.

Official records show how Lord Truscott used the Lords as a platform to defend Mr Putin after his decision to invade Georgia last year.

Last night, the 49-year-old peer refused to respond to the latest disclosures.

But Tory MP Patrick Mercer, an adviser to the Government on security matters, said: 'I would like some assurances that Lord Truscott's activities are wholly in the interests of Great Britain.

'Since Lord Truscott is not willing to address these matters it is incumbent on the Labour Party to do so.'

Truscott is one of four Labour peers investigated by police after he was recorded by undercover reporters claiming that for £2,000 a day he could influence legislation by 'identifying people...meeting people, talking with people'. He denies any wrongdoing.

In just 13 years, Lord Truscott rose from political obscurity as a borough councillor in Colchester, Essex, to a seat in the House of Lords.

But the most astonishing aspect of his rapid ascent is that it can be traced to a single day in the summer of 1991: the day he met his wife Svetlana, then 24, in Leningrad, now known as St Petersburg, just before the Soviet Union collapsed.

According to the couple's version of events, it was a chance meeting and love at first sight. They married and settled in Britain.

From that moment Truscott's career took off. With the striking and upwardly mobile Svetlana at his side, he became an expert on Russia, and a well-known figure in defence and intelligence circles in Russia, Brussels and Britain, while their social and financial fortunes soared.

Before that meeting, Truscott's political career had apparently stalled. The Oxford graduate, then 32, was living in lodgings and had a modest salary working on a project for the homeless.

An official who worked with him in the Labour Party said: 'He was a slippery character. He was like a bar of soap. He would be Left-wing talking to one person and Right-wing talking to another.

'He was a very average councillor. Nobody was more shocked than I to discover he had become a Lord.'

Just before he went to Russia, Truscott was selected as Labour's Parliamentary candidate for Torbay in Devon. He had virtually no chance of winning and, in the event, came third, ironically enough losing to Tory MP Rupert Allason, better known as spy writer Nigel West.

However, the contest would have focused Truscott's mind on marriage, as a wife would have been a big asset in such a conventional constituency.

On August 1, 1991, his marriage to Svetlana was reported by the Colchester Evening Gazette in terms as romantic as any Barbara Cartland novel. It said Truscott 'noticed Svetlana as soon as he stepped off the plane at Leningrad Airport - she was meeting a group of colleagues'.

It went on: 'He introduced himself and soon she was showing him around her home city during his week's visit. It was virtually love at first sight, because when it was time for him to leave, they realised they had to meet again. So Svetlana came to Colchester in May to visit Peter. 'Soon after, he proposed to her and the couple married in June... Some of the heartiest congratulations the couple received came from the Soviet Embassy in London.'

In the account given to the paper, the Truscotts said their grasp of each other's language was so slight that they could barely communicate. 'She had only learnt a few English phrases, while he only knew a few words of Russian,' it said. Svetlana also said that she approved of her new husband's politics: 'The Labour Party is popular in the Soviet Union as it is the party of the ordinary person,' she told the paper.

It is not known whether Truscott went to Russia hoping to find a bride, but, intriguingly, a former friend recalls his interest in Russian women.

'I remember seeing him with a brochure containing mail order Russian brides,' said the friend. 'It had photos of Russian girls who wanted to meet English men with a view to marriage.' There is no suggestion that this is how he met Svetlana. His trip to St Petersburg raises a number of questions. As a Labour Parliamentary candidate it is inconceivable that he would not have been monitored by the Soviet authorities.