Updated March 12, 2018 17:28:13

Photo: US stocks have enjoyed a strong rally following the presidential election. (Reuters: Jim Young, file)

US President Donald Trump has offered a preview of his 2020 election campaign, announcing his new slogan will be "Keep America Great!".

He told a crowd in Pennsylvania that he could not use "Make America Great Again" because it was no longer relevant after his time in office.

"We can't say 'Make America Great Again' because I already did that," Mr Trump said.

"Our new slogan when we start running in, can you believe it, two years from now, is going to be 'Keep America Great' exclamation point."

Mr Trump made his comments at a rally for Pennsylvania congressional candidate Rick Saccone, while boasting about the US economy's performance during his tenure and slamming Democrats and the media.

"All I do is good stuff. The economy is the best it has ever been," he said.

"The task for all of us … is to make sure that this great American comeback continues full-speed ahead.

"But we can only do that if we elect people who are going to back our agenda and fight for our values."

Mr Trump announced his intention to seek a second term in office last month, naming his 2016 campaign's digital director Brad Parscale as his 2020 campaign manager.

Topics: us-elections, donald-trump, government-and-politics, elections, united-states

First posted March 12, 2018 16:33:31