THERESA May will today insist that Brexit “must bring us together as a united country” as she announces a new Conservative Government would means-test the winter fuel payment.

Launching her party’s manifesto, “Forward, Together,” in a Labour marginal in northern England, the Prime Minister says in its foreword the process of EU withdrawal means the next five years will be the most challenging of her lifetime and will "define" the country.

“Now more than ever, Britain needs a strong and stable government to get the best deal for our country…[and] to make the most of the opportunities that Brexit brings.”

She adds, above all, Brexit will require a “unity of purpose stretching across this precious Union of nations…For as we embark on the momentous journey ahead of us over the next few years, our shared values, interests and ambitions can – and must – bring us together as a united country.”

The document will include a new headline commitment to increase social care funding south of the border.

Mrs May will announce how the Tories would means-test the winter fuel payment to ensure it was paid “only to the least well-off pensioners”.

What many will regard as a leftward shift will come as a surprise, not least to the Conservative-supporting grey vote, and will open up an argument on means-testing other allowances such as free TV licences.

The winter fuel payment is paid to more than 12 million people a year in a lump sum of up to £300; it is meant to help with the costs of winter heating.

Under the 2016 Scotland Act the allowance was devolved to the Scottish Parliament.

Neither Labour nor the SNP has proposed means-testing it but the Liberal Democrats have.

Facing what many insist is a crisis, the UK Government has announced an extra £2 billion for the social care system south of the border and has allowed councils to raise more money for care by increasing council tax.

There are no details about at what level of income the means-testing of the winter fuel payment will kick in or how much money is hoped to be transferred to social care. The Treasury spends up to £3 billion a year on the payment.