The reason for that is clear: British foreign policy is based on allowing proxy forces to overthrow Assad in a way that endangers the lives of Allwite Shia, Druze and Christian communities.
Another reason is that Britain, due to the long term impact of Thatcher's decimation of Britain's manufacturing, made London and The City, as well as the property boom, the engine of economic growth.
Capital from Qatar is responsible for the grotesque 'Shard" now completed in London, a building of atrocious vulgarity that produces an alienating effect upon Londoners. They own 20% of Barclay's Bank.As Mark Almond has commented
"Britain used to “protect” the Persian Gulf state. Now the Emir helps our economy out in return for backing his foreign policy.... Last year their special forces blazed a trail for democracy in Libya and they are helping rebels in Syria. But back home, the micro-state’s security services take a close interest in any sign of dissent. Six out of seven people are Third World migrant workers — many of them women — with no real rights".
This foreign policy of tacitly supporting such a gimcrack yet rich regime ( simply because the al Thani clan sat on oil, shames Britain as such as potentially destabilises the Arab world.
Britain urgently needs to reduce its over dependence upon oil in corrupt and volatile land. The promotion of public transport and the rejection of Thatcher's "Great Car economy" are part of that solution.