The Defence Secretary Gavin Williamson is set to announce more British troops will be sent to Bosnia.
Around 40 extra personnel will be deployed to the EUFOR operation in Bosnia & Herzegovina, Operation Althea.
The UK troops will join a specialist surveillance and intelligence taskforce during the country’s presidential and parliamentary elections in October.
Speaking to Forces News at the second day at the NATO Defence Ministerial in Brussels, Mr Williamson said:
“We’re going to be working as part of a much wider UN initiative just to make sure that the elections are free and the elections are fair."
The UK troops will operate alongside EU partners and NATO allies as part of Operation Althea to promote safety, security and stability in Bosnia & Herzegovina for six months.
Operation Althea is a 600-strong European Union Force mission commanded by NATO.
As well as committing to that operation, the UK also has approximately 30 troops as part of the NATO Kosovo Force, working with allies Germany, Italy, Turkey, Poland and the US providing intelligence, surveillance and reconnaissance capabilities.
Mr Williamson said: “Britain has been involved in Bosnia and the whole region for the last 25 years.
“I think we’ve got a responsibility to make sure things run smoothly and make sure that we have as much stability in the region as possible.”
It’s thought troops will focus on preventing Russian interference in the elections, though Mr Williamson did not comment on this.
It's expected that NATO allies will continue to support Afghan forces, with world leaders - who are set to meet again next month - believed to have agreed the extension of funding until 2024.
NATO Secretary General Jens Stoltenberg said:
"Taking substantial decisions on deterrence and defence, on projecting stability and fighting terrorism, and on cooperation with the European Union.
"This meeting has shown NATO’s unity despite any differences or issues such as trade, we continue to stand united around our core task.
"So I think we once again show that despite disagreements on issues like trade or the Iran nuclear deal, NATO is able to stand united around our core task to protect and defend each other."