The GMB union has sent out ballot papers to hourly-paid shop floor workers in Rocester over a switch from weekly pay to a monthly wage system.

Most members have rejected the firm's proposal of interest-free loans to help them in the transition, the union said.

JCB said the monthly pay plans are in line with "other global companies".

'Factory shutdown'

A further 300 ballot papers have gone out to JCB's factory in Wrexham.

Workers have until 5 July to register their vote, the GMB's senior organiser, Keith Hodgkinson, said.

The union said: "JCB informed the GMB that the move would take place in April 2007.

"But through representation, because there is a factory shutdown in July and August, we argued it should be during that time.

"Earlier this year the company offered loans of �800 for day workers and �1,500 for the higher earners on shift patterns.

"The offer was put to GMB members, but it was rejected in a consultative ballot."

A JCB spokesman said: "Already, 70 per cent of JCB's hourly paid employees in the UK are paid monthly.

"The change is also aimed at streamlining the payroll system and accommodating everyone under one structure.

"To make the transition as easy as possible for those affected, the company has offered interest free loans of up to �1,500, which can be repaid over a maximum of two-and-a-half years."