More than 150 years after the links between Scotland and Malawi were first established by Dr David Livingstone they are in danger of becoming looser.

That is the warning from politicians, charities, schools, aid workers and churches.

Their complaint centres on a new visa system introduced by the Conservative-Liberal Democrat Government at the end of last year. Experts warn this involves a series of hurdles that mean many prospective visitors to the UK from Malawi cannot even complete the application process.

Included is a requirement to secure biometric data and post a passport to another country, to Pretoria in South Africa, as well as to pay for the application in South African Rand. But one of the biggest stumbling blocks is that the system is cashless.

Credit card use is much lower in Malawi, for a whole host of reasons, than in a country like the UK, experts warn. The result is that where there is need there will be sharks.

A new sector of the economy has opened up - devoted to helping people get a visa, for a hefty fee. These intermediaries allow Malawians to pay in cash and then make the onward electronic transfer. But the costs can be enormous, and prohibitive. Campaigners warn that even the basic cost of a visa is around is £144.

This makes the cost of even applying to come to the UK the equivalent of more than 30 weeks pay for the average person, and there is no refund if it is unsuccessful.

The problem is affecting schools, churches, aid bodies and groups across Scotland, according to campaigners. One charity has found that the visa system is affecting training for Malawian workers in aid projects in the country, making it harder for them to come to its headquarters in Scotland.

Carol Findlay, from the Church of Scotland, says that even the church's partner institutions and Synod Offices in Malawi do not have a corporate credit card to use. Opponents say the basic outcome is that well-connected, wealthy Malawians, who find it easier to access Rand and cash transfer services, can come to the UK.

By contrast, aid workers and charity representatives are finding it harder and harder to develop the international links that they and their communities depend upon.

The issue has been taken up by Lord McConnell, the former First Minister, and Ton Greatrex, the Labour MP for Rutherglen and Hamilton West, the birthplace of Dr Livingstone, in the Commons and Lords.

For its part the UK Government rejects the claim poorly paid people are being discriminated against. Ministers insist that in the current economic climate it is not possible to provide application centres in every country and having part of the process in South Africa is better then the alternative - having all of it in South Africa. Ministers also say UK sponsors can pay the fees from this end, though campaigners say the system to allow them to do this rarely works.

The week before last Glasgow's Lord Provost Sadie Docherty spent time in Malawi, to see for herself how aid from the city is helping people. But the danger now is the chances of them making the return journey have become diminished.