Scotland risks entering any post-independence negotiations from a "position of weakness" and could emerge with relatively little influence on the world stage, the Scottish Secretary will tell an audience in America.

Michael Moore will say at an event at Washington DC's Georgetown University today that an independent Scotland would have "reduced clout" and "diluted influence" in European and world affairs, in contrast to the diminished but still "comparatively large, wealthy and powerful" United Kingdom.

In advance extracts from the speech, Mr Moore said Scots who vote Yes to independence risk "shedding influence over their own destiny".

The Scottish Government accepts Scotland would have to negotiate its European Union terms of membership but argues that this would be done from within as a continuing member state. But Mr Moore says that while the remainder of the UK is "likely" to continue in the EU, Scotland "would be required to seek membership".

Mr Moore will urge the pro-independence camp to explain how Scotland will then avoid joining the euro and setting up border controls with England.

Independence risks damaging the UK's "triple-lock guarantee" of an integrated domestic market, an expanding European market and a liberalising global market, he is expected to say.

It would "create new barriers" and "divide markets" in a similar fashion to the dissolution of Czechoslovakia in 1992, which saw exports from Czech Republic to Slovakia fall from 22% to 8%, and trade the other way drop from 42% to 13% of total exports within a decade, he will warn.

Mr Moore's speech comes after a Washington Post editorial warned Scotland would be "unable to contribute meaningfully to global security".

The editorial prompted a strong rebuttal from the SNP, culminating in an article by First Minister Alex Salmond in the US paper on Saturday challenging its factual errors and "disappointing" tone.

Mr Moore says: "Based on legal and academic opinion, the most likely outcome in the event of Scotland leaving the UK is that the remaining UK would continue as an EU member state.

"By definition, the remaining UK would be a smaller entity, shedding influence, but it would remain a comparatively large, wealthy and powerful player.

"Scotland, as a new state, would be required to seek membership, on negotiated terms, with the unanimous approval of every other EU member state.

"That means a smaller state, negotiating for influence, from a position of weakness."

A spokesman for Deputy First Minister Nicola Sturgeon, who is leading the Scottish Government's independence drive, said: "It is sad that Michael Moore should waste the opportunity of going to the States, and the time and expense involved, to talk Scotland down instead of promoting our country."