Foreign Secretary Margaret Beckett has condemned the apparent assassination of a Lebanese government minister in Beirut.
Mrs Beckett said the action "went against the interests of every single person" in the Middle East.
Industry Minister Pierre Gemayel - a prominent critic of Syria - was gunned down in a suburb of the Lebanese capital.
Speaking at a joint press conference with Israeli Foreign Affairs Minister Tzipi Livni in London, Mrs Beckett said: "Clearly we condemn it. We are dismayed. There are enough problems in Lebanon already."
Pressed on whether she thought Syria was likely to be to blame for the killing, Mrs Beckett said she had only just heard about the incident and needed to get "better information" from the region.
But she added that if it did turn out to be a targeted assassination, "I would simply say to whoever is behind it (that it) is absolutely against the interests of every single person in the region to have a maintenance of tension, an increase of tension".
She added: "Whatever the motives or whoever carried out an attack, they can't be acting in their own interests."
Ms Livni also emphasised that she had only just heard about the incident. But she added: "The negative role of Syria in Lebanon is not something new or unexpected.
"The news from Lebanon is another example of the kind of region, the kind of neighbourhood we are living in."
She said the conflict was between "moderates" and "extremists".
