News Ltd has publicly apologised to a former student politician who was branded a serial liar by Liberal powerbroker Michael Kroger after she had accused Opposition Leader Tony Abbott of physically intimidating her.

In a remarkable twist that could reignite debate about Mr Abbott's alleged punching of a wall after losing a student election in the late 1970s, News Ltd's barrister read an extended apology in the NSW Supreme Court on Monday on behalf of The Australian to the alleged victim of the intimidation, Barbara Ramjan, as part of a settlement of a defamation action.

Tony Abbott: accused of physically intimidating a woman. Credit:Alex Ellinghausen

In an essay by former Fairfax Media journalist David Marr, released last September, Ms Ramjan said that in 1977, after she beat Mr Abbott for the presidency of the Sydney University Student Representative Council, he put his face close to hers and punched the wall either side of her head.

Mr Abbott denied the incident occurred and a few days later, Mr Kroger described Ms Ramjan in The Australian and on radio and television as a serial manufacturer or false complaints, "a nutter", and "a nobody".