Campaigners gather in the main square at Dublin Castle as they wait for the result of the referendum on the Eighth Amendment. Photograph: Niall Carson/PA Wire

Dr Peter Boylan said the referendum result is a watershed moment for Irish women as he arrived at the RDS count centre.

Politicians and campaigners from the 'Yes' camp arrive at the RDS to a hero's welcome. Video: Enda O'Dowd

Ireland has voted to repeal the Eighth Amendment to the Constitution, which bans abortion, by an overwhelming majority. The Yes side won the referendum by 66.4 per cent to 33.6 per cent.

The total valid poll was 2,153,613, with 1,429,981 in favour of repealing and 723,632 against. Turnout was 64.13 per cent.

The news was formally announced at Dublin Castle on Saturday evening. Crowds had gathered in the castle’s main square ahead of the declaration.

Campaigners gather in the main square at Dublin Castle as they wait for the result of the referendum on the Eighth Amendment. Photograph: Niall Carson/PA Wire Taoiseach Leo Varadkar, FG TD Catherine Noone, and Minister for Health Simon Harris, at Dublin Castle. Photograph: Dara Mac Dónaill/The Irish Times As results came in on Saturday from across the country, they had indicated that people had voted overwhelmingly in favour of removing article 40.3.3 of the Constitution of the Republic and regulating the termination of pregnancy.

Earlier tallies confirmed the finding of an exit poll for The Irish Times by Ipsos MRBI.

– Full live results here

The exit poll suggested the victory for the Yes side in the referendum would be 68 per cent to 32 per cent.

Galway East became the first constituency to report an official result, with 60.2 per cent of voters choosing Yes, to 39.8 per cent for No. Galway West later saw a Yes vote of 65.95 per cent to 34.05 per cent for No.

Cork South-Central also voted Yes, by 68.84 per cent to 31.16 per cent, while Cork North-Central saw a Yes victory of about 64 per cent to 36 per cent. Cork North-West saw a Yes vote of 60.10 per cent, and Cork South-West recorded a Yes vote of 64.51 per cent. Cork East saw a Yes vote of 64.12 per cent.

Donegal was the only constituency to vote No, at 51.87 per cent.

Minister for Health Simon Harris said this was an extraordinary day for Ireland and for women from across the country. Photograph: Cyril Byrne/The Irish Times As the results came in people laid flowers and wrote notes of sorrow and gratitude at a mural of Savita Halappanavar at the Bernard Shaw pub in Dublin. Her death, following a septic miscarriage in October 2012, at Galway University Hospital, gave rise to several campaigns to repeal the Eighth Amendment.

Government reaction On Saturday Taoiseach Leo Varadkar and Minister for Health Simon Harris said they now expect legislation providing for abortion to be published by the end of July and implemented by the end of the year. Mr Harris said he hoped the Bill will be published by the summer recess and introduced in the autumn.

The Government proposals allow for abortion on request up to the 12th week of pregnancy and in limited circumstances after that.

Mr Varadkar described the expected result as “the culmination of a quiet revolution that’s taken place in Ireland for the past 10 or 20 years. This has been a great exercise in democracy, and the people have spoken.”

The Taoiseach said the results so far showed the nation was united, not divided. Mr Varadkar said the stories from women and men about how the Eighth Amendment had affected them was key to the outcome.

Speaking again after the declaration of the official result, the Taoiseach said: “We all want to ensure that there are fewer crisis pregnancies and fewer abortions. We will continue to improve access to sexual health and education to reduce crisis pregnancies and abortions further in the year ahead.”

Mr Harris called it an extraordinary day for Ireland and for women across the country. He said that women will breathe a sigh of relief and that the compassion we knew Ireland had had been recognised.

“The Eighth Amendment abandoned women in crisis,” the Minister said. “Women have been told, ‘Take the plane,’ ‘Take the boat.’ Today we say, ‘Take our hand.’ Women have been told, ‘You are on your own.’ Today we say, ‘We stand with you.’ ”

Vivienne Knight Hughes, from Balbriggan, keeping tally with baby Méabh Hughes at the Dublin county referendum count centre in Citywest, Dublin. Photograph: Dara Mac Dónaill/The Irish Times Watershed Dr Peter Boylan, the chairman of the Institute of Obstetricians and Gynaecologists, said this was a watershed moment for Irish women and a message to the 170,000 women who have had to travel for abortions outside the State.

Mr Boylan said he was not surprised by the scale of the result, calling it a message to Ireland’s women that they are valued. He said the focus now shifted to ensuring the legislation is effective and robust.

Members of the No side told The Irish Times they accepted the result.

John McGuirk of the Save the 8th campaign said he had “made peace” with the result. It is an overwhelming majority for Yes and a clear message from the electorate, Mr McGuirk told The Irish Times, adding that the No side could not have done anything differently.

Counting of votes in the abortion referendum. Photograph: Cyril Byrne Activists react at the count centre as votes are tallied following yesterday’s referendum in Dublin, Ireland. Photograph: Clodagh Kilcoyne/Reuters “Very, very sad day” Before the official result was announced, the LoveBoth spokeswoman Cora Sherlock described the apparent landslide for the Yes side as a “very, very sad day for Ireland”. Ms Sherlock said she was very disappointed that early counting appeared to confirm the Irish Times and RTÉ exit polls.

Speaking at the Dublin city count centre, she said that she was surprised by the size of the Yes vote and that during the campaign the public was “constantly being fed this idea that Ireland was not a safe country without abortion”, which was “not a true reflection of the facts”.

There were emotional scenes in the RDS as the results trickled in. Mary Lou McDonald, the Sinn Féin leader, said this was a grassroot campaign in which the people led and the politicians followed. She said her party would now consider a motion updating its policy to ensure it is in line with the Government legislation.