Saeed Ajmal's bowling action has undergone "a substantial improvement" since his last official test but will need more work to bring it within the 15-degree limit, the Pakistan Cricket Board has said. The update on Ajmal's action came after an unofficial test at Loughborough, which is one of ICC's newest accredited centres for testing illegal actions.

Biomechanist Dr Mark King, who tested Ajmal in Loughborough, submitted a report to the PCB which said: "The bowler has clearly modified his bowling action substantially. There is clearly a substantial improvement from the previous official test where the average elbow extension was 40 degrees but the amount of elbow extension is still over the 15-degree limit, but it is likely that with additional work the bowler can bowl within the 15-degree limit."

Ajmal, who turned 37 last month, was banned from bowling in international cricket by the ICC in September. He was reported after the first Test of Pakistan's tour of Sri Lanka in Galle this August. Subsequent testing of his action at an ICC-accredited facility in Brisbane found his average elbow extension to be more than twice the permissible limit.

Since then, the bowler has undergone a rehabilitation programme at the National Cricket Academy under the supervision of former Pakistan offspinner Saqlain Mushtaq. While a speed gun and two cameras were recording his movements, assessment of the remedial work was based largely on human judgement as Ajmal was working without the aid of a biomechanical lab at the NCA.

The PCB informed that the test in Loughborough was conducted according to the standard ICC Illegal Action Testing Protocol, which is used to assess the degree of elbow extension from the point of the upper arm horizontal to ball release within the bowling action.

Ajmal will now remain in England for another work and will work with Saqlain at the latter's cricket academy in Leicestershire. The PCB intends to apply for an official retest of Ajmal's action before the 2015 World Cup.