A defamation case brought by ex-Labour employees against the party is expected to be settled in the High Court later.
Labour is being sued by seven whistleblowers who appeared on a BBC Panorama programme last year criticising the then leadership's handling of anti-Semitism complaints
They argue attempts were made by the party to undermine their reputation.
Since becoming leader in April, Keir Starmer has sought to emphasise his commitment to tackling anti-Semitism.
In the July 2019 programme, entitled Is Labour Anti-Semitic?, a number of former party officials alleged that senior figures close to the leadership at the time had interfered in the process of dealing with anti-Semitism complaints.
They also claimed they had faced a huge increase in complaints since Jeremy Corbyn became leader in 2015.
In response, a party spokesman denounced them as "disaffected former staff" who had "personal and political axes" to grind. They were also accused of trying to undermine Mr Corbyn.
Seven of the whistleblowers took legal action and have asked the Labour Party formally to apologise in court.
Some allies of Mr Corbyn, who stood down in the Spring after four years leading the party, have urged his successor to fight the case.
But Sir Keir has been anxious to emphasise his commitment to root out anti-Semitism, committing to implement in full the recommendations of an inquiry by the equality watchdog into Labour's culture and internal procedures due out in September.
He recently sacked Rebecca Long-Bailey from the shadow cabinet for re-tweeting an article containing what he regarded as a conspiracy theory.