Zimbabwe's four rebel cricketers who had been included in a squad of 17 to prepare for the first Test against Sri Lanka boycotted a training session on Wednesday.

Former captain and fast bowler Heath Streak, left-arm spinner Ray Price, batsman Trevor Gripper and all rounder Sean Ervine failed to attend the net session at Harare Sports Club, where the opening Test will start on Thursday.

"None of those players were at nets today," Zimbabwe team manager Babu Memen told Reuters.

The four are part of a group of 15 rebels who have refused to make themselves available for selection until the Zimbabwe Cricket Union (ZCU) agrees to binding arbitration.

The rebels, most of whom are experienced players, want arbitration on the end of Streak's tenure as captain, the composition of the Zimbabwe selection panel and alleged poor conduct by ZCU officials.

The ZCU has offered mediation, which is not binding, to try and resolve the dispute but the move was rejected on Tuesday by the rebels, who have renewed their boycott.

Lovemore Banda, the ZCU's media manager, declined to comment on the issue on Wednesday.

The rebels met with their lawyer, Chris Venturas, on Wednesday and are expected to issue a letter formally rejecting the ZCU's offer of mediation later in the day.