AP News Guide: What to know about the Qatar crisis

DUBAI, United Arab Emirates (AP) — Qatar likely faces a deadline this weekend to comply with a list of demands issued by Arab nations that have cut diplomatic ties to the energy-rich country, though its leaders already have dismissed the ultimatum.

Here's a look at the ongoing crisis, the worst to grip the region since Iraq's 1990 invasion of Kuwait.

Qatar is a nation about the size of the U.S. state of Connecticut which juts out like a thumb on the Arabian Peninsula into the Persian Gulf.

The four nations have also pointed to Qatar's close relationship with Iran, with which it shares a massive offshore gas field that provides the peninsular nation its wealth.

The U.S., which has some 10,000 troops stationed at Qatar's sprawling al-Udeid Air Base as part of its campaign against the Islamic State group and the war in Afghanistan, also has sought to end the crisis.

Qatar has yet to retaliate, but could shut down an undersea natural gas pipeline running to the United Arab Emirates, a crucial power source for a desert nation that relies on desalination plants for water and air conditioners to cope with the scorching heat.