Please help me to understand this sentence

[Angie8]

Hi,
I'm reading a book and there's one sentence I don't quite understand, especially for the phrase "to suggest otherwise" in the sentence as shown below:

"Every attempt by Cameron or Osborne to suggest otherwise seemed merely to reinforce the idea that they were being less than ‘authentic’."

Anyone please help me to explain it? Thanks so much!

[probus]

This sentence must have an antecedent proposition or hypothesis, something that someone has claimed to be factual or true. To "suggest otherwise" is to propose an alternative.

For example, I might claim that the climate change we seem to be experiencing is a result of human activities. If you disagree and propose another explanation you are "suggesting otherwise."

[Angie8]

This sentence must have an antecedent proposition or hypothesis, something that someone has claimed to be factual or true. To "suggest otherwise" it to propose an alternative.

For example, I might claim that the climate change we seem to be experiencing is a result of human activities. If you disagree and propose another explanation you are "suggesting otherwise."

I see, thank you so much!