Britons on low incomes are being forced to live apart from their families because of new immigration rules that rate their marriages as "second class", campaigners say.

New Home Office regulations that have been in force since July mean millions of people earning less than £18,600 are unable to get visas for partners from non-EU countries.

Since the changes, thousands of British citizens who previously would have been granted a spousal visa are forced to choose between ending their relationship, splitting up their family or attempting to live abroad.

The income threshold is above average earnings in parts of the country, including the north-east. Immigrants' rights groups claims the new rules have created a two-tier system that rates the marriages of wealthy people higher than those of the less well-off.

Don Flynn, director of the Migrants' Rights Network said: "Being able to start a family in your own country should not be subject to the amount of money somebody earns."

"These measures create a two-tier system: those who are rich enough to live with whom they choose and those deemed to be too poor to live with somebody from abroad."

Next week a group of cross-party MPs and peers will launch an inquiry, chaired by shadow Equality Minister Kate Green into the impact of the new family migration rules.

Speaking to The Independent ahead of the launch, Ms Green said: "Women, young people, people with disabilities will find its harder to meet this threshold and find it harder to bring in family members. We want to look at what the impact is on families and on community integration."

A UK Border Agency spokesperson said: "To play a full part in British life, family migrants must be able to integrate – that means they must speak our language and pay their way. This is fair to applicants, but also fair to the public.

"British citizens can enter into a relationship with whomever they choose but if they want to establish their family life here, they must do so in a way which works in the best interests of our society."

Case Studies: 'A price on love'

“We just want to be ministers together”

Ashley Prodgers, 30, and Teya Tikaradze, 22

I met my wife, who is from Georgia, while training to become a minister in the Salvation Army. We got married in June, weeks before the visa changes. Teya is here on a religious workers visa, helping me run a community church in Addlestone. When that expires she'll have to leave the country unless we meet the new requirements. I get about £7,000, along with accommodation, as part of my commitment to the church, but the new guidelines don't take that into account. It may not seem like much, but it's enough to live on. We just want to be ministers together serving our community. Every person should have the right to live with the person they love.

"A lot of people don't need £18,600 to live"

Keith Thomas, 68, and Barbara Riley, 65

I met my fiancée on a pen-pal site 18 months ago. I wasn't looking for romance, but she came from America we realised we were in love and wanted to spend our lives together. The problem with the £18,600 threshold is that a lot of people don't need that much to live. We have about £1,200 a month between us and it's enough. I dread to think about if the law doesn't change.

"This approach puts a price on love"

Les Hudson, 43 and Becky Hudson, 33