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Although the United Kingdom has an adversarial political system, there have often been areas of agreement or bipartisanship between the two main parties at the time, currently Labour and the Conservatives, on a number of issues. This may extend to other parties, like the Liberal Democrats or Scottish National Party. Areas of agreement have tended to include Foreign policy and policy towards Northern Ireland.
There is also a convention within British politics to have formal and semi-secret cooperation facilitated by both parties parliamentary whips and senior civil servants, a process often referred to as the usual channels.