Prime Minister Lee Hsien Loong joined 400 people in an iftar - the breaking of the daily fast during Ramadan - at the Al-Muttaqin Mosque in Ang Mo Kio yesterday.
He shared a meal with religious leaders, and community and grassroots volunteers of different races.
Before the meal, Mr Lee was given a tour of the mosque, which can accommodate 3,500 people after its renovations were completed in March. Facilities like ramps for barrier-free access, and 500 more prayer spaces were added.
Minister-in-charge of Muslim Affairs Yaacob Ibrahim told reporters that Mr Lee said the mosque design was very welcoming and refreshing.
Dr Yaacob, who is Minister for Communications and Information, said: "During the fasting month... we open our doors to people of all races and backgrounds."
He added: "Coming together over a meal is always a good occasion and iftar offers this coming together of Singaporeans, foreign workers and people of all races."
This practice of giving blessings to everyone is central to the holy month of Ramadan, he said.
Terrorist attacks contradict this very ethos, he added in a strong condemnation of the London Bridge knife and van attacks last Saturday.
He said: "For this to happen during the holy month is appalling. No one can accept it."
Dr Yaacob also urged Singaporeans to stay vigilant and tell the authorities as quickly as possible if they notice anyone around them becoming radicalised.
"It is a collective effort," he added.
He was asked if the cut in diplomatic ties between Middle Eastern countries and Qatar would affect Singaporeans making the pilgrimage to the holy city of Mecca.
He said the Government is in consultation with the relevant parties and hopes pilgrims liaise with their travel agents on their journey.
"These are commercial arrangements. But if they have to divert, the agents will probably work with them to make sure they are able to fulfil their religious obligations."