Polygamous marriage is flourishing as the Government admits for the first time that nearly a thousand men are living legally with multiple wives in Britain.

Although the families are entitled to claim social security for each wife, no one has counted how many of them are on benefits.

Ministers appear to be ignoring the separate practice of unauthorised polygamy, which is said to have become commonplace in some Muslim communities. The Ministry of Justice admits that it has no estimates of numbers for these unions, which are often presided over by an Islamic cleric.

A senior Conservative MP and immigration expert called for action last night to end the scandal of women being pressured into entering unrecognised marriages with no rights.

“The Government has no grip on the situation,” said Humphrey Malins, the former Shadow Home Affairs Minister and founder of the Immigration Advisory Service. “This is quite clearly exploitation of women.”

MPs and peers have struggled for years to extract figures from ministers about the extent of polygamy. The first official estimate was made in response to a freedom of information request by The Times asking for statistics on benefits that are paid to wives who share a husband.

“It is estimated that there are fewer than 1,000 valid polygamous marriages in the UK, few of whom are claiming a state benefit,” the Department for Work and Pensions said. “Because of the small numbers concerned, our IT systems do not specifically record such information.”

The Government has long reassured Parliament that its policy is to prevent the formation of multiple marriages by refusing to allow second wives entry into the country. Under British law, husbands and wives can have only one spouse at a time. Multiple simultaneous marriages constitute bigamy, a criminal offence.

Britain does recognise polygamous marriages that have taken place in countries where the custom is legal, such as Pakistan, Nigeria and India. The Home Office said that multiple wives in polygamous marriages may be allowed into the country as students or tourists.

Officials are advised to let extra wives into Britain even if they suspect that a husband is trying to cheat the system by getting bogus divorces.

“Entry clearance may not be withheld from a second wife where the husband has divorced his previous wife and the divorce is thought to be one of convenience,” an immigration rulebook advises.

“This is so, even if the husband is still living with the previous wife and to issue the entry clearance would lead to the formation of a polygamous household.”

Opposition politicians are concerned about the burden being placed by polygamy on the social security and tax systems.

A husband may claim housing benefit for each wife even if she is abroad, for up to 52 weeks, as long as the absence is temporary and for pressing reasons. In a draft Commons reply released under the Freedom of Information Act, officials explained another way in which the system made it easy to receive handouts.

“A polygamous marriage is the only circumstance in which an adult dependency increase is payable in income-related benefits,” it stated. “In any other circumstances an adult ‘dependent’ would have to make a separate claim.”

To calculate the amount of income support that is payable to an extra wife, officials subtract the rate paid to an individual from that paid to a couple. This produces the amount that a cohabiting spouse is deemed to need in social security benefits. If a man lives with two valid wives, his household is paid the rate for a couple, plus an amount for the extra spouse, the documents show.

Women who enter unrecog-nised multiple marriages in Britain are far more vulnerable. They can end up being dumped by their “husbands” with no safeguards.

Mr Malins asked the Government three years ago to reveal how many unregistered polygamous weddings took place in Britain, but he did not receive an answer. Now officials admit that they do not know.

“I’ve not been able to find out from the Government what the extent of the problem is,” Mr Malins said. “It’s a very serious issue.”

The practice is said to have become commonplace, at least among Kashmiris, a group that accounts for most of the 747,000 Pakistanis in Britain.

Muslims believe that the Prophet Muhammad practised polygamy. One of his motiva-tions was thought to have been charity, taking on widows in time of war.

In contemporary Muslim countries, patriarchal attitudes may leave a woman and children defenceless if they do not have a man to protect them.

Asian republics that were part of the former Soviet Union have debated the legalisation of polygamy to save war widows from being forced into prostitution and human trafficking. Tajikistan has an estimated 25,000 widows. Kyrgyzstan rejected an attempt to legalise polygamy this March.

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