(Reuters) - Northampton Saints hooker Dylan Hartley has failed to recover from a knee injury in time to be named in England head coach Eddie Jones' first training squad for the upcoming World Cup in Japan, the BBC reported.

Hartley, who captained England to back-to-back Six Nations titles in 2016 and 2017, has not played since December and the BBC said his omission had increased the chances of him missing the World Cup.

Experienced scrumhalf Danny Care and flanker Chris Robshaw are also expected to miss out on the 29-man training squad that Jones will announce later on Thursday after slipping down the England pecking order, the BBC added.

Care, who has 84 England caps, did not feature in this year's Six Nations, while Robshaw has not played for his country since having knee surgery in October.

Jones can only pick players who were not involved in last month's English Premiership semi-finals for his first training squad, because all those who were have been put on mandatory rest for five weeks.

Players from losing semi-finalists Gloucester and Northampton Saints will join the camp next week and Jones will name his final training party, including players from Premiership finalists Exeter Chiefs and Saracens, on July 4.

The Rugby World Cup kicks off on Sept. 20 with England facing Tonga in their opening Pool C encounter in Sapporo two days later.

(Reporting by Hardik Vyas in Bengaluru; Editing by Simon Jennings)