"We have worked hard but I am not the kind person who is easily satisfied. This is not to say that we have not faced challenges, but never before had we faced a scenario where we were defeated in five states. So, we must increase what we are already doing."
Najib stressed that this was why the party could not have the attitude that it was "business as usual".
"We must have the realisation that we have to do something out of the ordinary in terms of strategy, plans and programmes, and also our role in the social media.
"We want to beat the state governments that are led by the opposition. In those states, we must put in more effort. This is my message: we must be more united, then we will stand a better chance."
This chance was being augmented by the winds of change, which Najib said he saw as favouring Umno and BN, even in the states the party had lost.
"My hope is for the momentum to be intensified. So, let's not feel that victory is in our hands, not yet, for as long as we feel that we can do more before polling day is upon us -- in many ways and from many different angles. This is the attitude all Umno leaders must have."
Najib said though Umno was a long-established party, voters would not gauge it based on its glorious history but expected to know its present and future struggle.
"This is why I want to emphasise that every Umno leader needs to have leadership values that people are at ease with, enabling them to win greater public support."
Najib also cited the issues that Selangor faced.
"In less than four years, the opposition government in Selangor has made many mistakes and caused many problems. I have described the things they have promised and not fulfilled and we must repeat these things because if we don't, the people will not realise that they've been lied to in the previous election and they shouldn't be lied to again."
On allegations by the opposition meant to confuse the people, Najib said the government could only act within the law.
"When the government implemented the Bantuan Rakyat 1Malaysia because we succeeded in increasing the national revenue to a record RM26 billion within a year, the opposition accused us of being irresponsible. Actually, they are the ones who made populist promises.
"They also alleged that I had met with armed forces heads to do something unconstitutional should Umno and BN lose. This is a lie, but they are willing to do this so that even if they cannot convince the people, at least they can mislead them."
Najib said the way some allegations were presented online made it difficult for the authorities to take action.
"However, if there is enough evidence, the government will carry out an investigation."