Theresa May has insisted she intends to "get on with the job" of being Prime Minister at a "really critical time in the UK".
Mrs May's latest comments come just hours after she revealed she intends to stay on as Prime Minister to fight the next election.
Speaking to ITV News while visiting Japan, Mrs May repeated that she is "not a quitter."
Responding to a question from ITV News Political Correspondent Carl Dinnen during a joint press conference with Japanese Prime Minister Shinzo Abe, Mrs May replied: "I said I wasn't a quitter, and there's a long-term job to do, there's an important job to be done in the United Kingdom.
"We stand at a really critical time in the UK."
In an attempt to show that her administration would not be defined by Brexit, Mrs May insisted she was tackling "long-term challenges" to reform the economy and tackle "injustices" including in mental health care.
"These are real issues that we need to be dealing with and I'm there to do it," she said.
"For most members of the public, they would say they want the Government to get on with the job and that's exactly what I and the Government are doing."
Thursday's comments from the Prime Minister echoed those she made on Wednesday to ITV when the 60-year-old told ITV News she was "in this for the long term" amid speculation about her future in the role.
Her hopes of remaining as Conservative leader have appeared doomed since her gamble on a snap election backfired.
Speaking on the first day of a three-day diplomatic trip to Japan, Mrs May said she was aware of the rumours that she could be replaced as the leader of the Conservative Party.
But she rejected the talk of her standing down or being replaced in Number 10.
"Yes, there has been an awful lot of speculation about my future which has no basis in it whatsoever," she told Dinnen, adding: "I'm in this for the long term."
Asked if that means she is not going to quit before the next election, she replied: "I'm not a quitter."
Many of Mrs May's Cabinet members are thought to be starting to jockey to replace her, while her latest pledge to remain as Prime Minister has met with mixed reaction from senior Tories.
She is widely seen as living on borrowed time after the damaging June election that saw her party lose its working majority in the House of Commons.
Foreign Secretary Boris Johnson - who is viewed as a potential Tory leadership candidate - said Mrs May had his "undivided" support, adding that she was "ideally placed" to deliver Brexit and he was "here to support her".
Senior Tory MP Nigel Evans, who was scathing in his criticism of the Tory campaign after Mrs May's election gamble backfired, insisted that the Prime Minister's vow to continue was "great news".
"We need no more instability whilst the PM focuses on disentangling the UK from the EU," he said.
"We have the right leader and PM to deliver this for us."
However, former cabinet minister Nicky Morgan said it would be "difficult" for the Prime Minister to lead the party into the next election, due in 2022.
Speaking to the BBC, Ms Morgan explained that while no leader wants to put a date on their departure in advance because it is a sign of "your own political mortality", she added: "I think it's going to be difficult for Theresa May to lead us into the next general election."
While former party chair Grant Schapps said it was "too early" for Mrs May to talk about going "on and on" like Margaret Thatcher.
Mr Shapps said that he did not "think there's an appetite for leadership elections right at this moment", adding that the Prime Minister should be judged on her performance in the Brexit negotiations, but it was "probably the case" that nobody wanted Mrs May to face Jeremy Corbyn at the ballot box again.
He told BBC Radio 4's Today programme: "I think colleagues may well be surprised by this interview last night and I think it is too early to be talking about going on and on, as Margaret Thatcher once said. Let's get some progress for the British people first, I think that's the priority."
On Wednesday, Mrs May maintained she was enthused by the challenges of the current Parliament.
She said there was a "real job to be done" in the UK, including getting the "Brexit deal right" while building a "deep and special partnership" with the European Union.
With a nod to her trade discussions in Japan, Mrs May said:"But it's also about building global Britain, trading around the world.
"Yes dealing with injustices that remain in the United Kingdom.
"But also going out around the world ensuring that we can do those trade deals that bring prosperity to our economy and bring jobs to the United Kingdom."