The finance minister meanwhile announced Sg$48 billion (US$33 billion) in fresh stimulus, taking to about Sg$55 billion the amount so far pledged by the government to help the export-reliant financial hub weather the downturn.
One of the world's most open economies which is viewed as a barometer for the health of global trade, Singapore is now heading for a deep recession this year after shrinking 2.2% on-year in January-March.
"COVID-19 is like an economic tsunami hitting Singapore's shores,” said Selena Ling, head of research and strategy at the city-state's OCBC Bank.
Singapore is one of the first economies to report growth data since the virus outbreak began, and the dismal figures add to signs the world is heading for a deep, painful recession with more than 3 billion people now under lockdown.
'Canary in the mineshaft'
The Singapore economy's 2.2% contraction was the worst quarterly, on-year figure since 2009 during the financial crisis, the last time the city-state was plunged into recession.
Compared with the previous quarter, gross domestic product (GDP) fell 10.6%, as all sectors of the economy were battered, according to advance estimates released by the trade ministry.
Announcing the new stimulus package shortly after the growth data's release, Finance Minister Heng Swee Keat warned Singapore was heading for its worst recession since independence in 1965.
"How Singapore manages this, and whether we emerge stronger from this, will define us as a people and a nation," he told parliament.
The city-state, a travel hub and financial center, is typically among the first countries to be hit during global crises because of its small and open economy, with ripples then spreading to other export-reliant Asian nations.
Singapore's latest growth data "is like the canary in the mineshaft, and warns of further economic pain to come for other Asian economies," said OCBC Bank's Ling.
The trade ministry further lowered its GDP forecast for this year, and said it expects the economy to shrink between 1% and 4%.
Even before the virus outbreak, Singapore's economy was already being hammered by the US-China trade war.
Singapore normally gives advance estimates before the quarter ends, but the figures do not cover the full period, meaning the revised reading – which will be released later – may be even worse.
Like many other places, Singapore has taken steps to contain the pandemic, including banning all foreign arrivals and closing bars and other entertainment venues.
But it has reported a relatively low number of cases – 631 infections, with two deaths – and has held off imposing a total lockdown so far.