Syrian government forces have blocked what would have been the first aid convoy to a besieged Damascus suburb for more than three years, BBC News reports.

The convoy had been given permission "from all parties" to proceed, the UN and Red Cross said.

About 4,000 people are thought to be trapped in the rebel-held suburb of Darayya.

Earlier this month, the UN said the Syrian government was refusing to allow aid to hundreds of thousands of people.

In a warning on Friday, May 13 Save the Children said that 12,000 people, a quarter of them children, were running out of food and medicine after the last route into the Khan Eshieh Palestinian refugee camp near Damascus was blocked.

Government forces shelled parts of Darayya on Thursday, the UK-based monitoring group Syrian Observatory for Human Rights (SOHR) said.

The suburb borders a military airport used by Russian planes in support of the government of President Bashar al-Assad.