Defence secretary Philip Hammond has said that the UK will be "putting a small team" in the British Baghdad embassy, to increase awareness and help plan for possible emergency situations.
Mr Hammond also said that the British government will only give "technical advice" to Iraq at this stage, which will be delivered through either military or civilian methods.
The statement comes after increased sectarian violence in the north of Iraq by Islamic militants.
The US State Department said it is increasing security at its embassy in Baghdad and will move some workers out of the Iraqi capital - but said a "substantial majority" of the embassy presence will remain.
"Some additional U.S. government security personnel will be added to the staff in Baghdad; other staff will be temporarily relocated - both to our Consulate Generals in Basra and Arbil and to the Iraq Support Unit in Amman," a State Department statement spokesperson said.
Americans are being evacuated from an airbase near Baghdad to escape the incursion from Islamist group ISIS.
Officials said three planes were set to leave Balad airfield in Sunni Muslim territory north of Baghdad, with ISIS militants sweeping south after capturing the city of Mosul yesterday.
Those being evacuated including 12 US service personnel and several hundred contractors, the Associated Press reports.
These dramatic photographs capture the explosion seen during a car bomb attack at a Shi'ite political organisation's rally in Baghdad.
The series of explosions killed 18 people, police and medical sources said.
Three bombs exploded in succession as people were leaving the rally, Reuters reporters at the scene said.
19 people have died after two bomb attacks targeted a commercial street and market in the same neighbourhood of northern Baghdad.
The attacked happened when a car bomb exploded in a commercial street in Azamiyah, killing 12 people and wounding 28, police said.
Minutes later a second bomb exploded near a market, killing seven and wounding 27.
At least 14 people were killed when a car bomb exploded near a church in southern Baghdad after a Christmas service on Wednesday, police and medics said.
The bomb went off in the Doura district while worshippers were leaving the church, police said, and most of the victims were Christian.
The death toll from a wave of bombings across Iraq today has risen to at least 62, officials said.
There were a series of car bombings in Baghdad, along with an explosion at a market and a suicide assault in a northern city.
Coordinated bombings in Iraq have killed more than 5,000 people since April.
The local branch of al-Qaida often takes responsibility for the assaults, although there was no immediate claim for Sunday's blasts.
At least 49 people have been killed in a day of bloodshed across Iraq, with 10 car bombs detonated across Baghdad and a suicide bomber attacking soldiers queuing up for their pay in the northern city of Mosul.
The attack on the soldiers claimed 12 lives after a motorist blew himself up outside a bank.
There was no immediate claim of responsibility for any of the coordinated blasts in Baghdad, which occurred in predominantly Shiite Muslim areas of the capital and left 37 people dead.
At least 37 people have been killed in a series of car bombs in Shiite districts across Baghdad, Reuters has reported, citing Iraqi officials.
Police and medics claimed 10 bombs were exploded, with the deadliest attack in a busy market in the town of Nahrawan, south of the capital.
At least 30 people have been killed in a suicide car bombing outside a cafe in the Iraqi capital of Baghdad, Reuters has reported, citing police and medical officials.
The attack occurred in the Amil neighborhood in a mainly Shi'ite district of the city.