WASHINGTON • White House counsellor Kellyanne Conway, one of US President Donald Trump's longest-serving aides, is leaving the administration at the end of the month, she said in a statement, citing family considerations.

Mrs Conway, the first woman to manage a winning presidential campaign, said in a statement that she is leaving to focus on her family.

Her husband George Conway said on Twitter that he is leaving the Lincoln Project, a political group committed to defeating Mr Trump's re-election in November.

"We disagree about plenty but we are united on what matters most: the kids," Mrs Conway said in the statement.

"Our four children are teens and tweens starting a new academic year, in middle school and high school, remotely from home for at least a few months," she said.

"As millions of parents nationwide know, kids 'doing school from home' require a level of attention and vigilance that is as unusual as these times."

She said the decision to leave was hers, and a person familiar with the matter said she informed Mr Trump on Sunday evening.

Over the weekend, the Conways' high-school-age daughter Claudia posted a series of tweets in which she said she was "devastated" that her mother is speaking at the Republican National Convention and suggested strife with both her parents.

She and her father both later tweeted that they were taking breaks from social media. Mrs Conway made no mention of her daughter's tweets. "In time, I will announce future plans," she said. "For now, and for my beloved children, it will be less drama, more mama."

The Republican convention kicked off yesterday with Mr Trump's renomination for president by delegates gathered in Charlotte, North Carolina.

Mrs Conway is still expected to speak at the convention tomorrow, according to a source.

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