The rules covering marriage for foreign nationals have changed as the government tries to stop sham marriages - but what do they mean in practice?
Arrests: Immigration officers raid a sham marriage
How are marriage rules changing?
From 1 February 2005, the rules governing marriage change for foreign nationals "subject to immigration control" - people who do not have complete and open residency in the UK.
In essence, the law now says foreign nationals who want to marry, be it to a British citizen or another foreigner, will now need government approval.
Those affected will be required to give notice of their marriage at one of 76 special register offices, rather than at any council. The "certificate for approval" for a marriage will cost £135.
Does this affect people from the European Union?
People from the EU have a right to freely live and work in the UK under rules that allow British people to do the same in other EU countries.
Some other European nationals are also exempt. Finally, the rules do not apply to foreign nationals who do not need a visa to be in the UK - typically someone who has been settled and working here for a long time or someone given refugee protection.
But it does affect everyone else from Africa to the United States and from Asia to Australia. The rules also apply to same-sex couples planning to use the new civil partnership laws.
So who is likely to get turned away?
Basically people with no right to be in the UK and people with a visa about to expire. If someone says they want to get married a month before their visa runs out, they will almost certainly be told they cannot because officials may assume that it is a sham marriage.
So what happens if someone is rejected?
Quite simply, if you do not get Home Office approval and you do not have permission to stay in the UK, a registrar will not give the go-ahead to a marriage.
Why is the government doing this ?
The Home Office introduced these new rules because it believes it needs to clamp down on fraudulent marriages networks used by people trying to avoid being removed from the country.
If you are foreign and marry a British or EU citizen, it enhances your rights to residency. Ministers say abuse has increased in recent years and registrars have been unable to stop suspect marriages.
Have they got a case?
Officials estimate there are 15,000 sham marriages every year, 8,000 of them in London.
There have been a number of high-profile raids of marriages in the past few years during which immigration authorities have broken criminal enterprises setting up fake marriages.
One recent case saw 25 people jailed for a sham marriage network stretching from London to Leicester.
Anecdotal evidence suggests it goes on among all communities and involves people from all walks of life, from manual workers in the black economy to graduates on gap years.
How do our laws compare with other European countries?
Registrars back the changes. They tend to say the law has been too lax in comparison with other European countries and these new rules will help them in their job.
Are these rules universally welcomed?
No - and they face a rough ride. The Joint Council for the Welfare of Immigrants says the rules are unfair and discriminatory against minorities.
The Joint Parliamentary Committee on Human Rights has some sympathy with that organisation's complaints - its report warned of a "significant risk" the law would contradict the European Convention on Human Rights and face challenges in the High Court.