Saudi Arabia has opened its land border with Qatar, and is set to reopen airspace and sea border, Kuwait has said. Qatar's only land border has been mostly closed since mid-2017, when Saudi Arabia, Egypt, the United Arab Emirates and Bahrain launched a blockade against the tiny Gulf state, accusing it of supporting Islamist groups in the region and of having warm ties with Iran. Kuwait has been mediating between Qatar and the four Arab states. The lifting of the embargo by Saudi Arabia paves the way for Qatar's ruler to attend a summit of Gulf leaders on Tuesday in the Kingdom.