Thousands of people have taken part in protests demanding abortion rights for Irish citizens after Dublin announced last week a referendum on the issue would be held in 2018.
The sixth annual March for Choice is believed to have been the biggest to date.
Thousands marched through Dublin city centre, while protests were also held in London, Manchester, Edinburgh, Glasgow and Brussels.
In Dublin campaigners gathered at Parnell Square from lunchtime on Saturday before making their way down the city's main thoroughfare, O'Connell Street.
Chanting and waving placards, demonstrators then marched along the River Liffey past the landmark Custom House before crossing the water on their way to the gates of the Irish parliament.
Anti-abortion activists staged counter events in the city and across Ireland to warn against relaxation of the current law.
Protesters were demanding the government repeal the eighth amendment to the Irish Constitution. The amendment affords equal rights to pregnant women and unborn children.
Added to the constitution in 1983, the amendment recognises an unborn child's right to life.
Terminations are currently only permitted when the life of the mother is at risk, and the maximum penalty for accessing an illegal abortion in Ireland is 14 years in prison.
In 2015, 3,265 women travelled from the Republic to England for a termination, according to official figures. Abortion is also effectively banned in Northern Ireland.
Linda Kavanagh, a spokeswoman for the Abortion Rights Campaign, said: "The reality is we have an instrument of violence against women written into our constitution, violence that is enacted every day on all pregnant people in Ireland.
"The eighth amendment has caused untold misery and damage, and it's time we removed it once and for all."
In London members of the London Irish Abortion Rights campaign made 205,704 chalk markings on the pavement outside the Irish Embassy to commemorate the 205,704 Irish women who have travelled to Britain for an abortion since the introduction of the eighth amendment in 1983.
Maeve O'Reilly, an organiser of the London protest, said: "We want to tell these women that we see them and we support them, and we want to show the Irish and Northern Irish governments that they cannot ignore this any longer."
The referendum on abortion is likely to take place in May or June next year, according to Taoiseach Leo Varadkar.
The decision was taken after a Citizens' Assembly, a body composed of 99 randomly chosen Irish citizens, recommended that women should have legal access to abortion.
However, pro-choice campaigners are concerned about the options voters will be given in the referendum.
The Abortion Rights Campaign said it would "reserve judgment on the announcement of a standalone referendum on the eighth amendment until we know the question that will be put to the people of Ireland".
It is feared that voters may be given the choice to amend, rather than repeal the eighth amendment.
Abortion is only permitted in Northern Ireland where the pregnancy threatens the life of the mother, or would adversely affect her mental or physical health.