The leaders of Afghanistan and Pakistan are due to hold talks with British Prime Minister David Cameron in London on the Afghan peace process.
Cameron initiated the meetings with Afghan President Hamid Karzai and Pakistani President Asif Ali Zardari last year, aiming to boost cooperation between the countries and promote regional stability.
The talks are expected to focus on preventing a Taliban resurgence in Afghanistan when British and other NATO troops withdraw from the country next year.
Cameron plans to dine with Karzai and Zardari at his country residence Chequers later Sunday, before holding formal talks with both leaders and their top officials early Monday.
Downing Street says the trilateral meeting will include Afghan and Pakistani army and intelligence chiefs for the first time.