Whether we like it or not, Hamas will win a sizable number of seats in the next election - they are becoming a political force in the Palestinian territories. It would be foolish to deny this and refuse meetings with an organization that one day could even appoint the next head of the Palestinians. Europe has (had) its share of terror organizations that have political wings (the IRA and Sin Fein probably being the prime example) and it learnt how to deal with them. Israel may not like it, so what - Israel depends on European money and Europe's goodwill, so it will moan and groan but in the end accept it.
Palestinian teen arrested for allegedly rioting in East Jerusalem (Haaretz)
from the article: Foreign Ministry protests EU contacts with Hamas officials