Keir Starmer will insist in a speech on Monday that Labour has changed under his leadership into a party British voters can trust.
Mr Starmer will admit in the first major speech of the election campaign that voters are not yet convinced Labour is fit to govern the country.
But according to early released excerpts of his speech, the changes he has made within the party mean it can be trusted with the public’s money and the country’s borders.
The Labour Party is ahead of Conservatives in the polls by about 20 points.
However, while voters have had enough of the Tories’ “failure, chaos and decline”, they are still not sure about Labour, Mr Starmer will say.
“Whatever the polls say, I know there are countless people who haven't decided how they will vote in this election.
“They're fed up with the full failure, chaos and division of the Tories, but they still have questions about us.
“Has labour changed enough? Do I trust them with my money, our borders and our security?
“My answer is yes, you can – because I have changed this party. Permanently."
Keir Starmer through the years - in pictures
“This has been my driving mission since day one. “I was determined to change Labour so that it could serve the British people.”
British Prime Minister Rishi Sunak has said Mr Starmer cannot be trusted because he has performed U-turns on policies.
Mr Sunak also claims Mr Starmer is a security risk because he served in Jeremy Corbyn’s cabinet at a time when the former Labour leader wanted to leave Nato.
In Monday’s speech, Mr Starmer will say his campaign is not just about a loss of faith in the Conservative Party, but more a positive vote for a changed Labour Party, directly telling voters: “I will fight for you.”
The Labour Party is ready to meet the “core tests” that British people expect from a government, he will say.
“The very foundation of any good government is economic security, border security and national security,” Mr Starmer will say.
“Make no mistake, if the British people give us the opportunity to serve, then this is their core test.
“I haven't worked for four years on this just to stop now.
“This is the foundation, the bedrock that our manifesto and our first steps will be built upon.”
A YouGov poll showed about six in 10 people (59 per cent) would be “unhappy” if the Conservatives won another majority, while 37 per cent would be “dismayed”.
