Travel expenses for sending the Secretary of State to celebrate St Patrick's Day in Washington have been revealed.
Brandon Lewis represented Northern Ireland at the annual White House celebrations this year in place of Arlene Foster and Michelle O'Neill, who cancelled their planned trip to focus on the coronavirus outbreak.
Figures from the NIO said the visit from March 10-14 cost taxpayers £6,531.57, covering travel, visas, accommodation and meals.
Mr Lewis made the trip shortly after taking over from Julian Smith.
The NIO sees the annual visit as a critical opportunity to engage with a range of key stakeholders in Washington DC.
Almost £15,000 of travel expenses for other senior civil servants in 2020 was also revealed, including those of former NIO permanent secretary Sir Jonathan Stephens.
After announcing his upcoming retirement at the start of the year, he took four working trips to Belfast in January and February costing £2,657 for his travel, accommodation and meals, as well as £195 spend on use of an official secure car.
His replacement Madeline Allesandri took seven trips to Belfast in February and March, costing a total of £2,343.
Expenses for NIO director Mark Larmour for trips to London and Dublin between January and February came to £3,218.
Fellow NIO director Colin Perry had the same expenses for four trips to Belfast between January and February.
Lindy Cameron, who had served as Sir Jonathan's deputy before being named as head of the National Security Cyber Centre, had expenses of £1,304 for travel to Wiltshire, Belfast and Dublin.
Last week Mr Lewis defended accepting donations from wealthy Russian individuals with links to President Vladimir Putin, insisting they were British citizens.
The Times listed Mr Lewis as having received £25,000 from Lubov Chernukhin, a banker and the wife of Mr Putin's former deputy finance minister, and £23,000 from Alexander Temerko, a former chief of a Russian arms company.
Mr Lewis said the donations had been properly declared.
A snap poll of Belfast Telegraph readers shows a massive majority in favour of Prime Minister Boris Johnson's ambitious plan to bridge the Irish Sea, linking Northern Ireland to the UK mainland for the first time since the end of the last Ice Age.