DOHA/KUWAIT (Reuters) - North Korean workers will start leaving Qatar and Kuwait after the Gulf Arab states said they would stop renewing visas, cutting off a source of foreign income for Pyongyang after U.N. Security Council sanctions and pressure from the United States.

U.S. President Donald Trump urged United Nations member states on Tuesday to turn up the pressure on North Korea to give up its nuclear weapons, using his maiden speech to the world body to address what he has said is the top global challenge.

The speech comes after North Korea’s nuclear tests and missile launches which have stirred global tensions.

Several thousand North Korean workers reside in the U.S-allied Gulf region, mainly working on construction sites. Kuwait hosts the only North Korean diplomatic mission in the region and this week took steps to expel the ambassador and downgrade ties.

Qatar, which is hosting the 2022 World Cup, said on Tuesday it was in full compliance with all U.N. sanctions and that it had stopped issuing visas to North Korean nationals following the previous round of sanctions in 2015.

“There have never been workers from North Korea working on any World Cup construction sites,” Qatar’s Government Communications Office said in a statement, adding some companies had employed North Koreans prior to 2015.

“Approximately 1,000 remain, but this number will decline rapidly as their employment contracts expire. Visas to North Korean nationals will not be renewed,” it said.

A source familiar with the matter told Reuters the majority of North Koreans working in Qatar were expected to leave in the first six months of 2018 as they come to the end of their employment contracts.

A North Korean source told Reuters on Monday Kuwait had given Ambassador So Chang Sik one month to leave the country, which hosts around 3,000 North Koreans.

The representation would be downgraded to a charge d’affaires, Kuwait confirmed on Monday, reiterating it had banned visas for North Koreans, halted direct flights and severed trade ties following U.N. sanctions in August.

A source in the Kuwaiti foreign ministry urged all sides to work toward a solution “that would avert destruction and warfare” state news agency KUNA said.

Kuwait’s moves follow a meeting between Trump and Kuwait’s ruler in Washington earlier this month and a joint statement from their foreign ministers on Sept. 8 which called on the international community to put further pressure on North Korea.

“The United States praised Kuwait’s positive steps in regards to implementing U.N. resolutions,” the statement said, in an apparent reference to the visa and flights ban.

Beyond its largest missions in Moscow and Beijing, North Korea also has major embassies in London, Rome, Stockholm and Berlin, as well as dozens of smaller embassies across Africa and Asia.