Given you are talking about actually processing personal data (suppliers' reps details), if this falls under the GDPR then it would be prudent to update the contracts to that effect (See Art 3 of the GDPR for full territorial scope, but this could mean a company based in the EU or processing data from EU individuals or companies). I believe the first step is reaching out to your Legal team and DPO and get an assessment specific to your business operations and identify the cases where you qualify as a data processor or controller. As a general approach, according to Art. 5 of the GDPR, you need to inform the individuals about collecting and processing their data, as well as the purpose of the data processing. Direct consent could also be required (see Art 7). If your organisation has already implemented the processes to comply with the GDPR, it would only be a matter of including it in the contracts or working with localised templates (i.e. include it only for your company's OUs or suppliers based in the EU).
Best regards,
Pablo Cilotta