A REMARK about "black people drowning" has cost a journalist at Yahoo! News his job.

The news service fired its chief political correspondent on Wednesday for the off the cuff remark made during the Republican Party's national convention.

David Chalian, the Yahoo! News Washington bureau chief, made the comment privately during a webcast of the Republican Party's national convention on Monday, but it was picked up by a live microphone.

With Hurricane Isaac approaching New Orleans as the convention got under way, Chalian was heard saying to an unidentified guest: "Feel free to say, they're not concerned at all. They are happy to have a party with black people drowning."

The remark was made over video of Republican presidential contender Mitt Romney and his wife Ann, and laughter was heard in the background.

Yahoo! said in statement that Chalian's remark "was inappropriate and does not represent the views of Yahoo!"

"He has been terminated effective immediately. We have already reached out to the Romney campaign, and we apologise to Mitt Romney, his staff, their supporters and anyone who was offended."

Chalian later apologised on his Facebook page for "making an inappropriate and thoughtless joke".

"I was commenting on the challenge of staging a convention during a hurricane and about campaign optics," he said.