The unexpected “mini-boom” in house prices continued in September, according to the latest official figures, but analysts have said that a slowdown in the pace of the recent rebound has begun.

Figures from the Land Registry showed a rise of 0.9 per cent in prices last month, taking the price of the average house in England and Wales to £158,377 and bringing the annual decline to 5.6 per cent.

However, estate agents have said that transaction levels remain low and have sunk further in the first few weeks of October as homebuyers and sellers begin to hunker down in the run-up to Christmas.

Rightmove reported that the number of new listings had fallen to 94,629 in October, from 105,924 in September, and the Royal Institution of Chartered Surveyors reported slight softening in demand last month.

The official data also masks huge regional variations in price performance. The Land Registry said that prices in London had risen the most and were up by 1.3 per cent. However, prices continued to slide in the North East and in Wales, down by 0.6 per cent and 2.6 per cent, respectively. Falls were steepest last month in Blaenau Gwent, down by 4.1 per cent in September, and in Middlesbrough, down by 3.9 per cent.

The housing market has had a run of good fortune in the past six months. From April to September, research by BNP Paribas Real Estate (BNP PRE), the consultancy, showed that nominal house price growth had reached more than 10 per cent. The best-performing regions, according to its figures, were East Anglia, where prices rose by 10.58 per cent, and Greater London, up by 9.66 per cent.

However, estate agents have said that the strong performance is confined to London and the South East and to prime country houses.

The head of one UK estate agency said: “The recovery is inside the M25. The market outside, in the real world of one-bedroom and two-bedroom flats, has not changed.”

Figures from Hometrack, the housing market analyst, show big variations according to property type and area in each region. For example, prices in the East Midlands have risen by 3.1 per cent in the past six months. However, within that, city-centre homes aimed at well-heeled professionals increased in value by 9 per cent, against a rise of 2.5 per cent for homes in disadvantaged urban communities.

In the South West, where average prices have risen by 4.8 per cent in the past six months, Hometrack found that while prices in the countryside were up 7.2 per cent, city-centre flats fell in value by 9.2 per cent.

Economists attributed the recent revival in house prices to sharply reduced mortgage interest rates and to more affordable prices after big falls from the 2007 peak, as well as a lack of new properties coming on to the market. As a result of the more favourable conditions, BNP PRE revised its 2010 forecast to predict price growth of up to 14 per cent in some regions next year, although it said that nationally, prices would rise by an average of 3.5 per cent.

Mike Rees, senior director of BNP PRE, said: “Market sentiment seems to support our view that there will be a gentle but cautious return to a long-term growth trend in 2010.”

However, with would-be first-time buyers still finding it hard to obtain a loan and with significant threats remaining to a full-scale recovery, other observers are maintaining a cautious view for the next few months.

Howard Archer, head of research for Global Insight, said: “We suspect that the current ongoing firming in house prices from their early-2009 lows will prove unsustainable and the rally will fizzle out before long.

“While interest rates are likely to remain very low for an extended period, the fundamentals for the housing market are largely unfavourable. Housing market activity is still at a low level compared with long-term norms, despite improving in recent months.”