UPDATE 2-Interserve says govt demand strong after solid H1

* Public sector, international unit proving resilient

* Weak auto, retail markets hitting private sector profit

* Made around 5 mln stg due to weakness of sterling in H1

(Adds company, analyst comment, shares, details)

By Rhys Jones

LONDON, July 10 (Reuters) - Building and maintenance firm Interserve (IRV.L) said demand for its services from government bodies was still strong after a solid first half but that it would continue to cut costs in parts of the business exposed to the slowing private sector.

"Central government work in the UK has held up well and will continue to do so as the reality of public spending challenges hit home," Chief Executive Adrian Ringrose told Reuters in an interview on Friday.

"However, the output of automotive and retail clients is down and some of our relationships are being mothballed, which is the source of the drop of revenue and profit in that area."

Interserve, which cleans Britain's crown courts and maintains government buildings, said in a trading statement on Friday that it had reduced costs at its facilities management and specialist services divisions given the tough conditions and had taken out a "few hundred" staff due to reduced demand.