LONDON — Frontrunner Varun Chandra has been dropped from the final list of three candidates to replace Peter Mandelson as ambassador to Washington.

Chandra, the favored pick of ministers and business-backers who wanted a “trade first” ambassador in D.C. to complete the U.K.’s tariff negotiations with the Trump administration will remain in Downing Street in an enhanced role – and continue with frequent visits to the U.S.

Chandra, whom No. 10 Downing Street had ranked as a leading candidate as recently as this week, was superseded in the pecking order by Nigel Casey, the U.K. ambassador to Moscow and Christian Turner, Britain’s designated representative to the United Nations.

A Foreign, Commonwealth and Development Office official familiar with the final shortlist process, and granted anonymity to speak freely, described a “massive fightback in the past days” to sway Prime Minister Keir Starmer towards a diplomat candidate and rule out Chandra.

They put the shift in direction in No. 10 down to a mix of “assiduous lobbying” about both the risks of another political appointee and the importance of a pick with security and tough negotiating experience – as well as the advantages of lifting Foreign Office morale in the midst of job cuts.

The key diplomatic post has been vacant since Mandelson, a long-serving Labour politician, resigned from the role amid fresh scrutiny of his friendship with late convicted sex offender Jeffrey Epstein.

Burning issues in the in-tray of the winner will including resolving a fresh dispute with the Trump administration over a flagship Tech Prosperity Deal the two sides landed on earlier this year — and which has been put on ice by Washington.

No. 10 has tried to downplay the spat, saying it is all part of “complex” and “active” discussions with the U.S.