Here is a transcript of House Speaker Nancy Pelosi's address to the nation announcing a formal impeachment inquiry of President Donald Trump.

Good afternoon. Last Tuesday, we observed the anniversary of the adoption of the Constitution on September 17th. Sadly, on that day, the Intelligence Community Inspector General formally notified the Congress that the administration was forbidding him from turning over a whistleblower complaint on Constitution Day.

This is a violation of the law. Shortly thereafter, press reports began to break of a phone call by the President of the United States, calling upon a foreign power to intervene in his election. This is a breach of his constitutional responsibilities.

The facts are these. The Intelligence Community Inspector General, who was appointed by President Trump, determined that the complaint is both of urgent concern and credible, and its disclosure, he went on to say, relates to one of the most significant and important of the Director of National Intelligence's responsibility to the American people.

On Thursday, the Inspector General testified before the House Intelligence Committee, stating that the Acting Director of National Intelligence barred him from disclosing the whistleblower complaint. This is a violation of law.

The law is unequivocal. The DNI staff, it says the DNI — DNI, Director of National Intelligence— shall provide Congress the full whistleblower complaint. For more than 25 years, I've served on the Intelligence Committee as a member — as the Ranking Member as part of the Gang of Four even before I was in the leadership.

I was there when we created the Office of the Director of National Intelligence. That did not exist before 2004. I was there even earlier in the '90s when we wrote the whistleblower laws and continue to write them to improve them to ensure the security of our intelligence and the safety of our whistleblowers.

I know what their purpose was and we proceeded with balance and caution as we wrote the laws. I can say with authority the Trump administration's actions undermine both our national security and our intelligence and our protections of the whistleblowers, more than both.

This Thursday, the Acting DNI will appear before the House Intelligence Committee. At that time, he must turn over the whistleblower's full complaint to the Committee. He will have to choose whether to break the law or honor his responsibility to the Constitution.

On the final day of the Constitutional Convention in 1787, when our Constitution was adopted, Americans gathered on the steps of Independence Hall to await the news of a government our founders had crafted. They asked Benjamin Franklin, "what do we have, a republic or a monarchy?" Franklin replied, "a republic, if you can keep it." Our responsibility is to keep it. Our public endures because of the wisdom of our Constitution enshrined in three co-equal branches of government serving as checks and balances on each other.

The actions taken to date by the President have seriously violated the Constitution, especially when the President says Article II says I can do whatever I want. For the past several months, we have been investigating in our committees and litigating in the courts so the House can gather all of the relevant facts and consider whether to exercise its full Article I powers, including a constitutional power of the utmost gravity, approval of Articles of Impeachment.

And this week, the President has admitted to asking the President of Ukraine to take actions which would benefit him politically. The action of the Trump — the actions of the Trump presidency revealed a dishonorable fact of the President's betrayal of his oath of office, betrayal of our national security and betrayal of the integrity of our elections.

Therefore today, I'm announcing the House of Representatives moving forward with an official impeachment inquiry. I am directing our six committees to proceed with their investigations under that umbrella of impeachment inquiry.

The President must be held accountable. No one is above the law. Getting back to our founders, in the darkest days of the American Revolution, Thomas Paine wrote that times have found us, that times found them to fight for and establish our democracy. The times have found us today.

Not to place ourselves in the same category of greatness as our founders but to place us in the urgency of protecting and defending our Constitution from all enemies, foreign and domestic. In the words of Ben Franklin, to keep our republic.

I thank our Chairmen, Chairman Nadler, Chairman Schiff, Chairman Nadler of Judiciary, Chairman Schiff of Intelligence, Chairman Engel, Foreign Affairs, Chairman Cummings Oversight. And Chairman Cummings, I've been in touch with constantly, he's a master of so much, but including Inspectors General and whistleblowers.

Congresswoman Richie Neal of the Ways and Means Committee, Congresswoman Maxine Waters of the Financial Services Committee, and I commend all of our members, our colleagues for their thoughtful, thoughtful approach to all of this, for their careful statements.God bless them and God bless America. Thank you all.

Shortly before Pelosi's public remarks, she made a statement in a meeting with her caucus. Read those remarks below.

Now, let me just put you in a place, I assume that you all know this, but just to confirm: last Tuesday was Constitution Day. Constitution Day, the day we observe and honor our Constitution. Sadly, on that day, was the day that news broke because of our leadership of Chairman Schiff of what the Republicans were doing.

Now, here it is: there is a complaint from a whistleblower about a conversation that the President had on the phone with a foreign leader. We know of at least one example and that is Ukraine.

The DNA – the DNI blocked by the Administration, has chosen to break the law. The law is very clear. It says 'shall' just as it does in the taxes. It says 'shall.' It doesn’t say may, should, could — 'shall.' The law is clear.

…

There is no question [President Trump] has admitted that he brought up the investigation of the Biden family in his call. He is asking a foreign government to help him in his campaign. That is a betrayal of his – our national security — and a betrayal of the integrity of our elections.

That is — that is really the essence of it.

Now, all of the work that has been done before by our Chairman – and I commend them... And, we had ourselves on a path, seeking the truth there, and that work must still go on.

However, if none of that had ever occurred, what has happened this past week is grievous and serious with our Constitution. And so, we must – it is understandable to the public. It has clarity in terms of what he did.

… But the quid pro quo — don’t get caught in the trap of oh there is no quid pro quo. No, he asked for assistance from the foreign government. That's wrong.

… But it would be my intention with the consent of this Caucus, to go forward in saying what the President has done and his betrayal of the Constitution challenges us to proceed with an impeachment inquiry.

… So, the Committees are tasked to do their work under an impeachment inquiry under oath.

But, right now, we have to strike while the iron is hot. This is a national security issue and we cannot let him think that this is a casual thing, so that's where I'm at.

… So, I know what the intent of the law was. And what the intent of the law was to secure, in cases like this, to secure our intelligence and to protect our whistleblowers.

… Let me just tell you this, I had a conversation with the President this morning. He said, 'you know, I don’t have anything to do with that.' I said, 'Well, then undo it.' Undo it. Because you are asking the DNI to break the law. I mean, it’s just outrageous.

In any event, our messaging is: the President admits to this. He doesn't even see anything wrong with asking a foreign government for aid. The President admits to this. He has taken this to another place of betrayal of his oath of office, our foreign policy, our national security and the integrity of our elections, therefore we are moving forward with this inquiry.

And, we want this to be done expeditiously. Expeditiously.

… Our founders understood that there could be some abuse of powers, they built guardrails into the Constitution. They never suspected that a President could undo the — nor did we when we were writing our bill on whistleblowers and DNI ever expect — that the Director of National Intelligence would disobey the law.