More than 100 lawyers are marching on Parliament on Wednesday to demand the weakening of divorce rules.
Resolution, a family law company, is leading the protest for "no fault divorce" to make it easier for couples to seperate. However a Christian lobby group has branded the campaign "naive" and accused the firm of undermining marriage.
Current divorce law dictates that unless a couple have lived seperately for more than two years, one side needs to atrribute fault - such as adultery or unreasonable behaviour - to the other as a reason for divorce.
Resolution says this is "unnecesarily complex" and forces couples to find a fault even when they don't want to.
"This often creates conflict and makes reaching a mutually acceptable agreement much more difficult," a statement from the organisation read.
Nigel Shepherd, national chair of Resolution, said: "Divorce is already difficult enough, we don't need it being made harder by the law pushing couples into conflicts and arguments.
"For so many to descend on Parliament to lobby MPs and Peers shows that it is time for politicians to act, and bring an end to the blame game."
The group say they are backed by the deputy president of the Supreme Court, the Family Mediation Task Force, and the relationships charity Relate.
But campaigners at The Christian Institute said liberalising the law would undermine marriage and make the UK's "appalling" divorce rate worse.
Simon Calvert, deputy director of The Christian Institute said, "Changing the law to facilitate quick no fault divorces is at best naive and at worst would further weaken the institution of marriage – the most stable form of relationship for raising children."
He said family breakdown was damaging for children and argued more than 10,000 couples file divorce papers each year but do not follow through with the split.
"Making divorce quicker and simpler would prevent these couples and many others from seeking help and pulling back from the brink. These changes would therefore see a significant additional number of divorces granted compounding the epidemic of human misery caused by family breakdown in this country."
He added: "Rather than weakening marriage, lawyers who often see at first hand the hurt and damage done by family breakdown should be arguing for schemes that back this great institution, such as compulsory marriage counseling and further financial support for married couples – proven measures that support stability and strong relationships, rather than undermining them."