The eyes of the world are on Syria as a ceasefire agreement continues to hold.
The Syrian government and rebels have signed up to deal brokered by the United States and Russia, despite concerns raised by rebels.
Hours before the ceasefire, Syrian President Bashar Assad said he is determined to recover all areas of the country from terrorist groups.
Foreign Secretary Boris Johnson has welcomed the Syrian ceasefire agreement and said the UK is ready to help make it work.
The former mayor of London made a telephone call to his Russian counterpart, Sergei Lavrov, in which the pair also agreed to meet on the sidelines of the annual UN General Assembly meeting in New York.
The UN's special envoy to Syria said that Bashar Assad's government was preventing life-saving deliveries during a national ceasefire.
The US and Russia have agreed on a cessation of fighting in Syria from 12 September and hope Syrian sides resume diplomatic negotiations.