Saudi Arabia, UAE, Egypt and Bahrain extend deadline by 48 hours, and foreign ministers will meet on Wednesday.

Qatar’s Gulf neighbours have given it until Tuesday to respond to a list of demands, after the original deadline passed on Sunday night.

Saudi Arabia, the United Arab Emirates, Egypt and Bahrain cut off ties with Qatar on 5 June, accusing it of supporting terrorism. On 22 June they issued a 13-point list of demands to end the standoff and gave Qatar 10 days to comply.

Qatar has called the charges baseless and says the stiff demands – including closing al-Jazeera and ejecting Turkish troops based in Qatar – are so draconian that they appear designed to be rejected.

According to a joint statement on the Saudi state news agency SPA, the four countries agreed to a request by Kuwait, which is mediating in the crisis, to extend by 48 hours Sunday’s deadline for compliance.

Foreign ministers from the four countries will meet in Cairo on Wednesday to discuss Qatar, Egypt said on Sunday

The blockading countries have not detailed any penalties to be imposed if their ultimatum is spurned, though UAE diplomats have suggested either suspending Qatar from the Gulf Co-operation Council (GCC), the regional trading bloc, or seeking to impose sanctions on countries that continue to trade with Qatar.

The western-backed, six-member GCC was formed in 1981 in the wake of Iran’s Islamic revolution and the outbreak of the Iran-Iraq war, by Saudi Arabia, the UAE, Kuwait, Qatar, Oman and Bahrain.

Since the crisis began last month Turkey has increased its military presence in Qatar in support of the emirate, and both it and Iran have delivered food supplies.

In one of the first signs that an extended blockade may have a significant impact on the country, some UK banks have ceased trading in the Qatari riyal for retail customers. Energy exports from Qatar, which is the world’s biggest exporter of liquefied natural gas, have not yet been hit.

The US, which has 10,000 troops in Qatar in its main Middle East base, has been split in its response between the White House and Department of State. Donald Trump has moved to rebuild Saudi ties, but the state department has tried to take a more nuanced role as mediator, working alongside Kuwait.

The White House said Trump spoke on Sunday night with senior figures in the region, urging unity and reiterating the importance of stopping terrorist financing and discrediting extremist ideology.

A state department official said on Sunday that the US encouraged “all parties to exercise restraint to allow for productive diplomatic discussions”.

Qatar said on Sunday that it would give its formal response to the demands on Monday in a letter to Kuwait. Qatari officials have repeatedly said the demands are so strict that they suspect the four countries never seriously intended to negotiate them, and were instead seeing to hobble Doha’s sovereignty.

Qatar’s Gulf critics accuse al-Jazeera of being a platform for extremists and an agent of interference in their affairs. The network has rejected the accusations and said it will maintain its editorial independence.