Translate the following English sentence to French:
"The next informal meeting of the Representatives Group on 14 and 15 April in Sintra, Portugal, will deal specifically with this issue which is problematic as there are no examples to follow."
La prochaine réunion informelle du groupe des représentants, qui aura lieu les 14 et 15, à Sintra, au Portugal, s'occupera spécialement de ce thème.