This week marked one year since the United States elected Donald Trump as its President, on the promise he would “make America great again”.

But on what should be a momentous, celebratory anniversary, Mr Trump continues to be dogged by allegations of impropriety and corruption. The most serious of the accusations – currently being investigated by a special counsel – is that he only won the top job because of Russian meddling.

It has been alleged that people working for the Russian Kremlin offered the Trump campaign dirt on Democrat opponent Hillary Clinton in return for a promise to overturn tough US anti-corruption laws.

It has been alleged that people working for the Russian Kremlin offered the Trump campaign dirt on Democrat opponent Hillary Clinton. (60 Minutes)

This Sunday on 60 Minutes, reporter Ross Coulthart speaks to those with inside knowledge on the allegations that – if proven – could see key members of Donald Trump’s inner circle could go to prison, and eventually, even the president himself.

Mr Trump has always denied scheming with the Russians during his election, however as Coulthart reveals, “it’s often the cover-up and not the actual crime that brings the candidate undone”.

“Investigators are still weighing the evidence on whether Trump or his campaign team did anything illegal to help swing the election by colluding with the Russians,” Coulthart said.

Mr Trump has always denied scheming with the Russians during his election. (60 Minutes)

“But right now the big question is Trump or any of his senior officials lying about what really happened."

Speaking to Coulthart for Sunday’s report is Vladimir Kara-Murza, the Russian insider spilling secrets so dangerous, Putin and his Kremlin want him dead.

Twice in the past two years he was deliberately poisoned, a cost that he believes has come due to his role as an outspoken Russian activist.

Russian insider Vladimir Kara-Murza has been repeatedly poisoned for his activism. (60 Minutes)

Kara-Murza details to Coulthart how Mr Trump could have been played in the Kremlin’s attempt to overturn a US anti-corruption law known as the Magnitsky Act – a human rights bill introduced by President Obama to punish Russian officials responsible for the death of lawyer Sergei Magnitsky.

The claim coincides with Russian lawyer Natalia Veselnitskaya’s visit to Trump Tower during the 2016 election campaign, where she met with Mr Trump’s son Donald Jnr, son-in-law Jared Kushner and campaign chairman Paul Manafort.

Mr Trump’s team claim the meeting was completely innocent, however Ms Veselnitskaya this week admitted there were promises made by Donald Trump Jnr that the Magnitsky Act could be reexamined if Mr Trump won the election.

As the allegations continue to grow in the investigation against the US President, the world watches on asking: could this be the end of Mr Trump? (60 Minutes)

As the allegations continue to grow in the investigation against the US President, the world watches on asking: could this be the end of Mr Trump?