Donald Trump, lagging behind Hillary Clinton in polls, has outlined what he would do in his first 100 days if he became US president.
With 17 days until the election, much of the recent focus has been on controversies linked to his campaign.
But in a speech in Gettysburg, Pennsylvania, he sought to highlight changes he would introduce, including were limits on lobbyists and a renegotiation on trade and climate change deals.
Restrictions would be placed on White House officials becoming lobbyists after they left office and there would be term limits for members of Congress.
Mr Trump said he would cancel all payments to UN climate change programmes and redeploy the funds to fix US infrastructure.
The Republican nominee would start of the process of "removing the more than two million criminal, illegal immigrants" and the denial of visa-free travel to countries who refused to take back their citizens
The speech was one of the most detailed by Mr Trump during his candidacy, and also touched on matters of security, economy and trade.
He said the country was facing a "fork in the road" over its future.
While some polls have shown he has eaten into Mrs Clinton's lead over the past week, after the third presidential debate, she is still leading him in a number of key swing states.
Before his speech, Mr Trump again attacked leading media outlets and suggested they were biased against him.
He vowed to break up media conglomerates, saying he would scrap the rumoured purchase of the Time Warner company, the owner of CNN, by AT&T.
However, those comments were made outside of his main speech, and it was not clear if they were being put forward as policy.
Mr Trump also said he would sue every woman who had accused him of sexual assault or inappropriate behaviour as soon as his presidential campaign was over.
Ten women have come forward to accuse him of inappropriate behaviour, in the weeks after a video emerged of him boasting of groping women and kissing them.
Mr Trump is trailing Mrs Clinton in most polls - although he has narrowed the gap according to a Reuters/Ipsos poll released on Friday.
Mrs Clinton maintained her commanding lead in the race to win the Electoral College, however, and claim the US presidency, a Reuters/Ipsos States of the Nation project poll released on Saturday showed.
- BBC / Reuters