Excerpt:
It is an unlikely setting from which to launch a fightback against Egypt's new military rulers.
But a cramped flat above a disused kebab shop in North London has become the focal point of the Muslim Brotherhood's effort to regroup after President Mohamed Morsi was forced from office and his movement declared a terrorist organisation.
In Cairo the organisation is facing one of the toughest crackdowns in decades: thousands of supporters have been arrested, while organisations linked with the Brotherhood have had their assets confiscated. Mr Morsi, who was Egypt's first democratically elected president, faces trial for alleged treason, and he has been joined in the country's notorious jails by the group's supreme guide and most of its senior leadership.