Delegates from more than three dozen countries traveled to Saudi Arabia to take part in the so-called Friends of Yemen conference.
Terrorism activity attributed to al-Qaida in the Arabian Peninsula, the Yemeni arm of al-Qaida, has escalated since a yearlong political crisis culminated with the resignation of longtime Yemeni President Ali Abdullah Saleh.
Visiting British Minister for the Middle East Alistair Burt said London is committed to leading in the international effort to help steer the "fragile progress" Yemen has made in political transition.
"What happens next matters to millions of Yemenis, but also has wider implications for the security and prosperity of the entire region and wider world," he said in a statement.
Delegates at the conference pledged to help Yemen work toward a national dialogue and develop plans for security reform.
Yemen's military is supported by U.S. forces. The CIA is allegedly targeting AQAP suspects using missiles fired from unmanned aerial drones.
Representatives at the Riyadh conference pledged to commit $4 billion in aid for Yemen.