GAZA, April 5 (Reuters) - Britain held on Thursday its first talks with a leader of the Islamist Hamas group, sending a diplomat to meet Palestinian Prime Minister Ismail Haniyeh to discuss efforts to free a BBC journalist abducted in Gaza. A British diplomat said Jerusalem Consul-General Richard Makepeace, who came to Haniyeh's Gaza office, would "just discuss the kidnapping" and the talks were not a departure from the European Union's policy of shunning Hamas. BBC correspondent Alan Johnston was abducted from his car on March 12. He has been held captive longer than any of the several foreign journalists who have been seized, and subsequently released, by gunmen in the Gaza Strip.