Stopping the rainbow flag being flown over the Foreign Office and embassies during Gay Pride events undermines efforts to promote human rights, MPs have warned.

William Hague allowed the international symbol to be raised atop his Whitehall headquarters as Foreign Secretary in 2014 but the practice ended when Philip Hammond took over the role.

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The FCO said it was "long-standing policy" only to allow the Union flag, other national flags and those of overseas territories to be run up diplomatic flagpoles - stressing the ban also applied to those of bodies such as Nato and the Commonwealth.

But the Commons Foreign Affairs Committee urged Mr Hammond to ignore the protocol and follow his predecessor's lead by restoring the rainbow - which is flown annually by some other Government departments.

His failure to do so in 2015 "sent a message that contradicts much of the actual work and objectives of the FCO", it suggested in a report on human rights.

"We recommend that the FCO reverses its decision not to fly the Rainbow Flag for national Pride events.

"In the absence of such events due to host nation intolerance of equality around sexuality, the FCO should fly the Rainbow Flag from missions abroad alongside the Union flag on IDAHOT Day (International Day Against Homophobia, Transphobia and Biphobia)."

An FCO spokesman said: "The Foreign and Commonwealth Office is committed to promoting and protecting the rights of LGB&T people. UK diplomatic missions around the world mark Pride Week in a number of ways.

"It is the FCO's long-standing policy to fly the Union flag, national flags and the flags of overseas territories. The Union flag always takes priority and is flown from the FCO's main flag pole at all times. It is never substituted for another flag."