Donald Trump has deleted some of the Twitter tirade he posted following President Barack Obama's re-election, and added new critiques of NBC's Brian Williams.

Trump tweeted a retort on Wednesday saying Williams "knows that I think his newscast has become totally boring so he took a shot at me last night." He added, "Wouldn't you love to have my ratings?"

He also deleted some of Tuesday night's tirade, including tweets calling for revolution and incorrectly saying that Obama had lost the popular vote. In a new tweet Wednesday, he said the election was "the Republicans to win" but that Republican Mitt Romney hadn't connected with voters.

Trump endorsed Romney in the presidential race and garnered publicity last year for questioning whether Obama was born in the US and eligible to be president.

The Celebrity Apprentice star recently promised to contribute US$5 million to a charity of Obama's choice if the president released his college and passport records.