Unmarried women who live with their partners are being "thrown on the scrapheap" without any financial support if the relationship ends, o ne of Britain's most senior judges has said.

The Government has failed to act on " inescapable" reform of cohabitants' rights and as a result women are being left with "nothing at all", even when they have spent up to 35 years with their partner, Sir James Munby, president of the Family Division said.

Sir James, who recently oversaw the formation of a single Family Court for England and Wales as part of a huge reform to the system, also suggested divorce proceedings in some cases should no longer have to go before a judge.

Speaking at a press conference at the Royal Courts of Justice, the judge said despite calls for an overhaul of cohabitants' rights dating back as far as 40 years, "nothing has happened".

He said: "Something has got to be done, that seems to me to be inescapable. In saying that, I'm saying no more than what judges have been saying for 40 years."

Sir James said a possible model would see the regime currently applied to divorced couples, applied to cohabitants, with appropriate adjustments.

Other systems could see either partner compensated from the adverse financial consequences of the collapse of the relationship.

The judge said: "One is aware, anecdotally, of these cases of cohabitation which have lasted 20, 30, 35 years and then breakdown, where there are children in the relationship and where the woman has made precisely the same career sacrifices, precisely the same financial sacrifices as many women do as a consequence of marriage.

"At the end of that process, the children if they're below the age of 18, are entitled to certain forms of financial relief but the woman in that case is entitled to nothing at all.

"She may be, to use the vernacular, thrown on the scrapheap, at a time when she has lost... because of her age, and because of the time she has been out of employment, where there's no way she can rebuild her career, in certain instances where had the parties been married she would have had a very significant claim to very significant financial relief."

Turning to divorce, Sir James suggested it could be time to remove the concepts of "fault" as a basis of divorce and leave irretrievable breakdown as the sole ground.

He also added it is time to consider whether divorce should become more of an administrative process in scenarios where there is no dispute.

The judge said: " Elsewhere, there are countries where the system is for divorce which is by consent and where there are no children it is treated as an administrative matter, dealt with by what using our terminology one might describe as the registrar of births, deaths, marriages and divorces. It seems to work."

Asked if the move would lead to a spike in divorce and undermine marriage, Sir James said: "It would make divorce no easier than it is at present.

"The reality is that we have, and have had for quite some time in this country, divorce by consent. In the sense that both parties wish there to be a divorce.

"If they're able to establish the grounds for divorce, which it is very easy to establish, the process is essentially a bureaucratic, administrative process, albeit one conducted by a district judge.

"Part of my thinking is that we should uncouple the process of divorce from the process of financial remedies, ancillary relief as it used to be called, following divorce, in the way the recent changes have actually finally uncoupled the process of divorce from the process of dealing with child disputes consequential upon the divorce."

On April 22, a single Family Court for England and Wales replaced three separate tiers of court that currently deal with family proceedings.

Other changes include a new 26-week time limit for care proceedings to further reduce excessive delays in these cases.

Reforms to the family justice system came after an independent Family Justice Review in 2011 found vulnerable and damaged children who were meant to be protected were having their ''futures undermined''.

Excessive delays, with care and supervision cases taking an average of 56 weeks, were among some of the problems identified by the review led by David Norgrove.