President Michael D Higgins has extended his sympathies and those of the Irish people to the victims of the terrorist attack in London.
“This latest terrible attack in London will be rightly condemned by all those who believe in the rights of our public to live their lives in the public space,” Mr Higgins said.
"To our neighbours in the United Kingdom I send the sympathy and support of the Irish people, and in particular the heartfelt sympathy to the families of those who have lost their lives, and our thoughts and wishes for such recovery as is possible to the injured and their families."
Tánaiste and Minister for Justice Frances Fitzgerald said the attack in London was “another depraved and cowardly attack on innocent people”.
“Our first thoughts are with the families of those killed and with the injured victims,” she said.
Ms Fitzgerald said she had been briefed on developments on Sunday morning by Garda Commissioner Nóirín O’Sullivan.
“The Garda authorities remain in close contact with their counterparts in London and will offer whatever support they can,” she said.
Minister for Foreign Affairs Charlie Flanagan said Ireland stands with Britain after seven people were killed and scores injured in the attack in London late on Saturday night.
Mr Flanagan said: “For the second time in two weeks, the ordinary people of the UK have been subjected to cowardly and barbaric attacks. Ireland stands with the UK and condemns these acts utterly.
“We continue to closely monitor the situation. Anyone who has serious concerns about loved ones in London can contact my Department in Dublin on 01 408 2000, or the Irish Embassy in London on 00 44 207 235 2171.”
Fianna Fáil leader Micheál Martin also expressed his sympathies to the families and friends of those who died or who were injured.
“This was a callous attack on people who were simply enjoying life,” he said.
“Fianna Fáil stands with the people of London. London has withstood attacks of this nature before, and it became stronger as a result. Last night’s attack will, I have no doubt, bring Londoners of all creeds, races, and ethnicities, even more together and will make the city even stronger.”
Sinn Féin president Gerry Adams said he absolutely condemned Saturday’s “horrendous attacks” .
“On behalf of Sinn Féin, I offer my sincere condolences to the victims and the families of those killed and injured and to the people of London,” Mr Adams said.
In the North, PSNI Chief Constable George Hamilton said his thoughts and sympathies were with the people of London following the “horrendous” attack. “We also send our support to our colleagues in the Metropolitan Police, City of London Police, British Transport Police and all the emergency services that responded last night,” he said.
US president Donald Trump took to Twitter amid the unfolding drama on Saturday to offer US help to Britain and to promote his controversial travel ban as an extra level of security for Americans.
British police rushed to two incidents in central London after a van plowed into pedestrians on London Bridge before attackers carried out multiple stabbings in the nearby Borough Market area.
"Whatever the United States can do to help out in London and the UK, we will be there - WE ARE WITH YOU. GOD BLESS!" Trump said in one of two tweets.
“We need to be smart, vigilant and tough. We need the courts to give us back our rights. We need the Travel Ban as an extra level of safety!” he said in the other.
Mr Trump's appeal for his travel ban followed his emergency request that the US Supreme Court reinstate the executive order that would bar people entering the United States from six predominantly Muslim countries. It has been blocked by lower courts.
Mr Trump was briefed earlier about the London Bridge incident by his national security team, according to White House spokesman Sean Spicer, who said on Twitter that security officials would continue providing the president with updates.
The US State Department also said it was monitoring the situation in London closely, and advised American citizens in Britain to heed the advice of local authorities and maintain their security awareness.
The president says the travel ban, a centerpiece of his 2016 campaign, is needed to protect Americans from terrorist attacks. Critics say his reasoning is flawed and assail the ban as discriminatory.
On Thursday, his legal team asked the high court to allow the March 6th executive order to take effect immediately despite being blocked by lower courts. The Supreme Court rarely grants emergency requests.