Work and pensions secretary Iain Duncan Smith has started to outline the details of a temperature test to be brought in for British expatriates.
The new measure will decide which citizens living abroad should be granted up to £300 a year in winter fuel allowances.
It is thought that some 100,000 people resident in the likes of Spain, France and Greece will lose the payment when the test is introduced.
This is designed to cut the annual bill for taxpayers by £17 million with those living in Portugal, Cyprus, Malta and Gibraltar all affected.
The south west of England, which has the warmest average temperature at 5.6C, will be used as the standard.
Any country that has a higher annual average temperature than this will see British expats go without the handout.
One exclusion will be Italy, as the north of the nation has a colder winter climate than the UK, bringing the whole country's average down.
Some 1,859 Brits will therefore still be able to claim the benefit, even if they live in the south of Italy, where it is generally much warmer.
It used to be the case that expats only qualified to receive the winter fuel allowance if they lived in Britain up to the age of 60, but a ruling by the European Court of Justice extended this to all British pensioners abroad.
This equates to some 444,000 people and costs the UK £100 million every year – a 13-fold increase over the last ten years.
Spain, where winter temperatures can be as high as 17C, has 49,443 expats getting the payment, while France with winter highs of 13C is home to 28,624 British pensioners.
Mr Duncan Smith said: "The winter fuel payment is intended to help British pensioners with heating costs. From winter 2015/16, we are changing the rules so that it no longer goes to people in European countries with an average winter temperature higher than the warmest part of the UK."