Defence Secretary Des Browne has hailed "significant" security improvements in Iraq on a visit to Baghdad which coincided with an upsurge in violence.
A suicide car bomb attack on the Interior Ministry in Baghdad killed at least 16 as Mr Browne met Iraqi prime minister Nouri Maliki to discuss the handover of control. Elsewhere, at least 19 Iraqi soldiers were killed in clashes in the southern city of Diwaniya.
Mr Browne said the challenge for those trying to build a peaceful and democratic Iraq was to hold firm in the face of redoubled efforts by insurgents.
"There has been a significant improvement (in Baghdad)," he told BBC Radio 4's PM programme.
"But of course the headlines will be grabbed by the events at the Ministry of the Interior and by the attack on Iraqi security forces by others.
"That's exactly what those people intend and I think we have to constantly remind people that this process is constantly being attacked by those who are determined not to see a successful government and a successful Iraq."
Mr Browne's visit came after senior defence officials revealed last week that Britain's military presence in Iraq could be halved within a year.
British forces have already handed over one province - al Muthanna - to the Iraqis, with a second - Dih Qar - expected to follow soon.
Mr Browne said security would not be compromised by any exit plan.
"We will not exit, or we will not transfer the responsibility for any part of Iraq to the Iraqis themselves, unless they are satisfied that the threat measured by us and by them is such that their own security forces can cope with it," he said.
