In her statement, Greening said the three main providers of abortion in England had already stopped charging women travelling over for the procedure and that they would be reimbursed for their costs incurred so far.
Ms Ewart argues that Northern Ireland's laws are incompatible with her rights under the European Convention on Human Rights. Greening's announcement means that women who earn less than £15,276 a year will be able to claim for travel and accommodation costs.
An attempt to change the law in Northern Ireland to allow abortions in cases of rape, incest or serious malformation of the foetus started in the UK Supreme Court on Tuesday with harrowing accounts of women's experiences.
Now in Northern Ireland, anyone that carries out an unlawful abortion faces life imprisonment.
Christian campaigners have reacted with disappointment after the United Kingdom government revealed plans to provide free abortion services in England for women from Northern Ireland, where terminations are heavily restricted.
Northern Ireland's strict abortion law subjects women and girls to "inhuman and degrading" treatment and discriminates against them on grounds of sex, the UK's highest court has heard.
Northern Ireland is the only country in the United Kingdom where abortion is illegal.
The Northern Irish Department of Justice and the Attorney General successfully appealed this ruling.
It will also rule on whether the Northern Ireland Act 1998 entitles the NIHRC to bring the proceedings under the Human Rights Act 1998 to seek a declaration of incompatibility.
He said: "It is the job of the Commission to promote human rights and in particular the rights of vulnerable groups like the disabled".
Ahead of the case, Ann Furedi, chief executive of Bpas, said it "illustrates how women in even the most desperate circumstances - women who are victims of sexual assault, women who have received a tragic diagnosis of a severe foetal anomaly - are denied access to abortion care in Northern Ireland".
Speaking on Monday, Ms Greening stated that her announcement did not affect the Government's position on the abortion laws in Northern Ireland.
"The UK Government's commitment to fund abortion care in England was a true landmark moment - but it is not the solution to the injustice of Northern Ireland's draconian abortion laws".
"What we ought to be doing is providing much more care and support for a woman who is facing a pregnancy and is in turmoil about it, not just throwing.it's short-sighted".
One of them, Ashleigh Topley, was told when she was four-and-a-half months pregnant in 2013 that her baby's limbs were not growing and she was going to die.
A panel of seven Supreme Court judges in London will hear arguments for and against the proposed changes during a three-day hearing.