WASHINGTON (Reuters) - President Donald Trump on Monday dismissed Democrats’ allegations of impropriety over Vice President Mike Pence’s stay at Trump’s Irish resort and over the U.S. military’s use of a Scottish airport near a Trump-owned golf course.

“I had nothing to do with the decision of our great @VP Mike Pence to stay overnight at one of the Trump owned resorts in Doonbeg, Ireland,” he wrote in an early morning tweet.

“I know nothing about an Air Force plane landing at an airport (which I do not own and have nothing to do with) near Turnberry Resort (which I do own) in Scotland, and filling up with fuel, with the crew staying overnight at Turnberry (they have good taste!). NOTHING TO DO WITH ME,” he also tweeted.

Democrats in the U.S. House of Representatives are looking into Pence’s stay at the Trump International Golf Club in Doonbeg on the west coast of Ireland, which is 180 miles (300 km) from the capital, Dublin, where his meetings were held.

Elijah Cummings, chairman of the House Oversight Committee, wants documents on the visit sent to the panel by Sept. 19. The House Judiciary Committee is also looking into the stay as part of an investigation of Trump’s proposal to host next year’s Group of Seven economic summit at his Florida resort.

Cummings is also concerned about Scotland’s Prestwick Airport, looking into purchase orders for fuel totaling $11 million and reports that the airport offered cut-rate rooms for select passengers and crew, as well as free rounds of golf at Turnberry to visiting U.S. military and civilian air crews.

In a statement, the Air Force said it would review all guidance related to the selection of airports and lodging accommodations during international travel.

“While initial reviews indicate that aircrew transiting through Scotland adhered to all guidance and procedures, we understand that U.S. Service members lodging at higher-end accommodations, even if within government rates, might be allowable but not advisable,” the statement added.

The U.S. Constitution bars government officials, including the president, from receiving financial benefits known as emoluments from foreign or domestic governments, without approval from Congress.

Trump has remained in control of his hotels, golf courses and other businesses, although he said he handed over day-to-day operations to his sons before taking office in January 2017.

His hotel down the street from the White House in Washington has stirred the biggest controversy. Trump opened the Trump International Hotel shortly before he was elected in November 2016 and it has become a favored lodging and event space for some foreign and state officials visiting the U.S. capital. In July, a federal court dismissed a lawsuit filed by Democratic attorneys general over the hotel, saying the case lacked legal standing.