Jeremy Corbyn has said Labour is "gaining a huge amount of ground" on the Conservatives in the battle to win the general election.
The Labour leader urged voters to "watch this space" despite opinion polls putting his party as many as 24 points behind the Tories ahead of the June 8 vote.
He continued efforts to shift the focus of the campaign away from Theresa May's call for voters to give her a Brexit negotiating mandate and on to Labour's aim of tackling inequality.
Speaking during a visit to a children's centre in Bristol, Mr Corbyn told Sky News: "We've just started the election campaign, we're 72 hours into it and I'm loving every moment of it.
"We're gaining support, we're gaining a huge amount of ground and we're getting a great deal of support.
"Watch this space."
He added: "We are putting a message out there – this country does not have to be so divided, [there] does not have to be such appalling levels of poverty and unachieved ambition because of people growing up in poverty.
"That's our message, that's the one we're putting out, and the Labour Party is totally united in putting that message out, okay?"
Mr Corbyn also revealed he had not decided whether he would stand down if Labour loses the election.
Asked if he had decided what he will do in the event of defeat, the Labour leader replied: "No decisions at all, what an absurd question.
"We're 72 hours into the election."
Hundreds of Labour supporters turned out at Whitchurch Common in Cardiff for Mr Corbyn's visit to Cardiff North, where he was joined by Welsh Labour leader Carywn Jones.
Mr Corbyn was heckled by some members of the crowd, shouting for him to stop Brexit, during the the early part of his 20-minute speech, but others told them to shut up.
He said that within a few hours of the general election being called, 2,500 people had joined the Labour Party, with thousands more joining in the last few days.
Mr Corbyn said Labour was the party of "hope and opportunity" for everybody, before speaking about his plans to abolish zero-hours contracts and to introduce a £10 an hour living wage for everybody.
Meanwhile British prime minister Theresa May is coming under pressure to spell out her plans for pensions, after failing to commit the Conservatives to preserving the "triple lock" guarantee after the general election.
Mrs May dodged a question on pensions at a campaign event where she committed the party to maintaining its controversial promise to spend 0.7 per cent of national income on international aid.
Chancellor Philip Hammond signalled that he wants the upcoming Tory manifesto to drop the party's pledge from the 2015 election not to raise income tax, national insurance or VAT over the life of the next Parliament.
Speaking during a visit to the IMF in Washington DC, the Chancellor told the BBC: "All chancellors would prefer to have more flexibility in how they manage the economy and how they manage the overall tax burden down [rather] than having to have their hands constrained.
"But what we put in the manifesto will be decided in the next few days and we will publish that."
Liberal Democrats accused the Conservatives of "getting their betrayal in early", while Labour leader Jeremy Corbyn highlighted the contrast between Mrs May's silence on pensions with his own party's commitment to keep the triple lock, which guarantees payments will rise annually by the highest of inflation, average earnings or 2.5 per cent each year.
Mrs May was asked during a visit to a factory in her Maidenhead constituency whether older people can expect to see their pensions continue to rise, if she wins the election, as they have done so far under Conservative-led administrations.
She replied: "What I would say to pensioners is, just look what the Conservatives in government have done. Pensioners today are £1,250 better off as a result of action that has been taken.
"We were very clear about the need to support people in their old age, and that's exactly what we've done."
Liberal Democrat frontbencher Alistair Carmichael said pensioners "should now realise that their pensions are not safe in Conservative hands".
"This is May and Hammond admitting that the cupboard is bare thanks to their disastrous hard Brexit," said Mr Carmichael.
"Theresa May's refusal to guarantee the triple lock is yet another massive U-turn by the prime minister. Conservative high command is clearly in total disarray as it attempts a handbrake turn every day, including on such major issues as immigration, foreign aid and the single market."
