Amicus, Great Britain's second-largest trade union, is close to securing an enterprise agreement with Nacco Materials Handling Group Europe.
An Evening Times report said talks were in progress after Nacco workers voted in favour of unionisation last month, despite management opposition.
"Management says they accept the decision and want to work in partnership with us. They are keen to talk to us and sort out an (enterprise) agreement," said Amicus spokesman Bernie Hamilton.
Nacco did not comment.