ASLEF's General Secretary Mick Whelan has warned that there is a "likelihood" that further strike action will be called.
Mr Whelan said a meeting will be held later this month to determine the next steps.
The union has reduced next week's strike dates from six to three because of public concern about the impact of a week-long halt to services.
Overtime is currently banned by the union which has affected services daily, leading to cancellations and delays.
The ban means there is currently a 25% shortage of drivers on Southern which explains the impact on services.
The Rail, Maritime and Transport union is also involved in a dispute with Southern over the changes to the role of conductors which has also led to strike action.
A six-day strike by Southern Rail drivers scheduled for next week has been cut to three days.
Members of the ASLEF union were due to walk out for the entire week from midnight on Sunday in a bitter dispute over driver-only trains.
Strike days will now be held on the 10th, 11th and 13th January.
Southern has today imposed its controversial policy of Driver Only Operation at the centre of the bitter nine month dispute.Read the full story ›
A choir full of people who once slept on the streets has played in Brighton this week - as new figure's show the city's homeless population has almost doubled.
Today the Government announced a new £1.25million grant to help tackle the 'homeless crisis' in the city. But campaigners say its not nearly enough.
Andy Dickenson reports and speaks to Arthur Richford and Emma Broomfield from the Choir With No Name, Cllr Clare Moonan of Brighton and Hove City Council, and Andy Winter of the Brighton Housing Trust.
The two sides in conflict over a tiny parcel of land have been battling it out in the High Court.
It centres on the site of a former roller rink in Whitstable. It's been publicly owned for fifty years ago, but could soon be the site of holiday homes.
Tony Green has been speaking with Suzanne Blaustone, of the Oval Chalet Preservation Community Group, and Colin Carmichael, Chief Executive of Canterbury City Council.
The former Ukip leader says he wants to be a bridge with the US but that Downing Street will not allow it.Read the full story ›
The Government estimated a 3% increase will raise £208 million in 2017/18, while a further hike in 2018/19 another £444 million.Read the full story ›
Conservative Tim Loughton, East Worthing and Shoreham MP, has asked for an assurance everything will be done to end a "nonsense of a strike" and "give our constituents their lives back".
At Prime Minister's Questions, Theresa May agreed that it was an "appalling strike" and suggested that Jeremy Corbyn should call Aslef, who donate to Labour, and tell them to call the "strike off immediately".
Half of Reading's children's centres could be closed as the council looks to make savings of millions of pounds.Read the full story ›
As a three-day strike by train guards on Southern Rail continues, ITV Meridian presenter Sangeeta Bhabra spoke to Alex Foulds, Deputy Chief Operating Officer Govia Thameslink. She began by asking him when the dispute was going to be resolved.