The typical UK property value was £216,000 in March, marking a 0.6% fall compared with February, according to the report released jointly by the Office for National Statistics, the Land Registry and other bodies.
Some experts pointed to signs of a "Brexit-related" slowdown, while others said house prices simply could not continue rising at some of the high levels seen in recent years.
There are also signs of a shift in the regions which are now driving house price growth, away from London.
The pace of house price growth continued to slow down on an annual basis, with a 4.1% increase in March, following a 5.6% rise in February. This marked the weakest annual growth rate since October 2013.
The price paid for a typical first-time buyer home also decreased month-on-month, by 0.4%. First-time buyers now pay around £182,407 on average, which is still 4.4% higher than a year ago.
In England, house prices have increased by 4.4% over the 12 months to March 2017, with the average price in England now at £233,000.
Within England, the lowest annual house price growth was in the North East, where prices decreased by 0.4% over the year, followed by London, where prices increased by 1.5%.
The East of England and the East Midlands showed the highest annual growth in England, with prices lifting by 6.7% over the year to March.
Richard Snook, a senior economist at PwC, said: "In a reversal of the normal regional pattern, the south of England showed some of the softest growth with price inflation of 2.8% in the South West, 3.8% in the South East and just 1.5% in London. This is the weakest figure for London since March 2012.
"These figures are consistent with the Brexit-related slowdown that we anticipated last year and our guidance of 2% to 5% growth this year."
Wales saw house prices increase by 4.3% over the previous 12 months to stand at £148,000.
In Scotland, the average price increased by 0.7% over the year to reach £137,000.
The average price in Northern Ireland stands at £124,000, having increased by 4.3% over the year.
Mark Harris, chief executive of mortgage broker SPF Private Clients, said the housing market in March was "bound to be quieter compared with a year ago", as last spring saw a rush of buy-to-let investors trying to beat a stamp duty hike imposed in April 2016.
Sarah Beeny, owner of estate agent Tepilo, said: "The slowdown in house price growth we are seeing is simply due to the fact that house prices cannot continue rising at the rates we have seen over the past few years.
"If the large rises we've experienced in recent years continued, the average house price would be almost double what it is now in 10 years' time, and that's just not realistic."