The situation in Washington has become more serious now that it was during the Watergate scandal of the 1970s, and investigators must get to the bottom of ties between the Trump administration and Russia, the former director of U.S. national intelligence James Clapper has said.

In a speech to Australia’s National Press Club Wednesday, Clapper said that allegations that U.S. President Donald Trump shared intelligence with the Putin regime were “very problematic” and that the Watergate scandal, which brought down former president Richard Nixon, “pales” in comparison.

“I lived through Watergate. I was on active duty then as a young officer in the air force and it was a scary time. But it was against the backdrop of all the post-Vietnam trauma, which seemed, at least in my memory, amplified the crisis in our system with Watergate.”

The Watergate scandal, considered one of the greatest political scandals of the twentieth century, refers to the U.S. government’s involvement in a range of illegal activities under the Nixon administration, including a break-in at the Democratic National Committee’s Watergate headquarters.

“I have to say though that I think when you compare the two, Watergate pales, really, in my view, compared to what we’re confronting now.”

Clapper’s comments in Canberra comes a day before former FBI chief James Comey is to testify to the Senate intelligence committee as part of an investigation into whether Trump’s campaign team colluded with Russian officials to influence the 2016 U.S. presidential election.

Comey had been examining allegations of Russian ties before he was abruptly fired by President Trump last month. Critics say that the dismissal was due to Comey’s refusal to comply with President Trump’s orders to stop an investigation into his advisers.

Clapper, who served under the Obama administration, described the dismissal as “egregious and inexcusable.”

“I characterize it as inexplicable. I don’t understand that,” he said.

“It is absolutely crucial for the United States, and for that matter for the world, for this presidency, for the Republicans, for the Democrats and for our nation at large, that we get to the bottom of this.”

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