More than a thousand Secret Service agents exceed pay caps due to Trump and family's frequent travel

The US Secret Service is facing a cash crunch because of the high cost of protecting President Donald Trump, his many homes and large family, its director said in an interview published Monday.

Randolph "Tex" Ailes, the service's chief, told USA Today more than 1000 agents have already hit caps for the year on salary and overtime pay because of the crushing workload.

With 150 foreign heads of state due to converge on New York next month for the UN General Assembly, demands on the service are only intensifying.

Mr Trump has travelled nearly every weekend to his properties in Florida, New Jersey and Virginia.

And the Secret Service also provides protection for his adult children on their business trips and vacations.

In all 42 people in his administration have Secret Service protection, including 18 members of his family.

"The president has a large family, and our responsibility is required by law," Mr Ailes said.

"I can't change that, I have no flexibility."

Mr Ailes, who is seeking more funding from Congress, says he is in negotiations with key members to raise caps on pay and overtime from US$160,000 (A$201,632) a year to $187,000 (A$235,576) for at least the remainder of Mr Trump's term.