Scottish Conservative leader Ruth Davidson has questioned the UK Government's goal of reducing annual net migration to below 100,000.

She has raised doubts about the policy in an article for the Daily Telegraph.

The Conservatives have consistently promised and failed to lower the number to the tens of thousands since taking office in 2010.

Davidson, who opposed leaving the EU in last year's referendum, said Brexit is a "big reset button" that should make lowering the number of migrants easier.

She added: "But we have to ask whether the target continues to be the right one?"

Citing low unemployment levels, she said the potential for economic growth was "facing ever greater limitations".

The Scottish Conservative leader also questioned her party's policy of counting international students as immigrants in the statistics.

She said: "If people don't think that students should be included in the net migration numbers, let's take them out.

"Currently, students can secure a post-study work visa if they secure a graduate-level job within three months of graduating. Should that timescale be extended?"

Davidson added: "Neither of the major parties of government has sought to have a meaningful and sustained discussion with the public about the merits and drawbacks of immigration.

"Since there will always be immigration and emigration, we Conservatives must start - and sustain - that conversation."

Labour's shadow Scotland Office minister Paul Sweeney said: "The Tories are in open warfare and these comments from Ruth Davidson show just deep the splits in the party run."