UK business schools have just eight weeks to make a case against the government’s proposed restrictions on post-study work visas, which will discourage talented overseas students from applying here.

This was one of the sobering conclusions of a panel of legal, academic and communications experts discussing the challenges facing “Brand Business School UK” at Tuesday’s UK Business School Communications Conference.

Immigration solicitor Maria Patsalos of law firm Mishcon de Reya summarised the Government’s proposed changes to the student visa system. The Home Office announced the changes on Tuesday.

The Home Secretary, Theresa May, has been charged with bringing migration to the UK down “from hundreds of thousands to tens of thousands”.

As part of this effort, Tier 2 visas for skilled workers with job offers will be capped at capped 20,700 from April 2011 to April 2012.

The cap excludes intra-company transfers – people being transferred by their employer from an overseas office to a UK office – after heavy lobbying by multinational companies.

Tier 1 visas for skilled workers with no job offer will also be capped or scrapped depending on the category.

There will be no cap on visas for Tier 1 visas for investors or entrepreneurs – groups who must invest in £1m or £200,000 in the UK respectively.

Visas in the general category, previously called he highly skilled migrant program, covering scientists, artists and academics will be capped at 1,000 per year.

Post-study work visas will be abolished as of April 2011. Currently, overseas graduates of degree-level programs in the UK are automatically eligible for a two-year work visa, and 38,000 were issued last year.

Patsalos said the proposed changes would “fewer opportunities to gain employment would obviously make the UK a less attractive place to study”.

Other speakers agreed, and warned of the long-term economic impact on the UK of turning talented foreigners away.

David Simmons, International development Director at Cranfield School of Management, said that UK business schools had been on the back foot at a recent admissions conference in Sao Paulo, Brazil.

While US and Canadian schools were confident about the work permits on offer to graduates – Canada also offer overseas graduates a two-year work visa – UK business schools had to say they “didn’t know” what would happen to students after they graduated.

Simmons pointed to a recent study by Nottingham Business School and the Association of Business Schools, that found that foreign students at UK business schools contribute £2 billion to the economy directly, and £7 billion indirectly. Putting them off would cause damage “that could last 30 or 40 years” to the UK’s economy and academic standing.

Sharon Bamford, Chief Executive of accreditation body AMBA (the Association of MBAs), said that UK higher education was still respected as a ”quality product” overseas, but had been undervalued by the government and by institutions.

From the introduction of higher fees for overseas students in the 1980s to the current restrictions on work permits, the UK had long sent mixed messages to foreign students about whether they were wanted or not. “As a result, may of the brightest people have gone to the US... and set up very successful businesses there,” said Bamford.

UK business schools could soon find that they are losing market share not only to the US and Europe, but to a growing number of institutions in India and China too, she added.

Catherine Marston, who covers international students and academics for industry group Universities UK warned that government planned to squeeze other aspects of migration and working in the UK that would affect students, such as cutting the hours of work permitted during term time.

Solicitor Maria Patsalos and political communications specialist Charles Lewington offered advice to business schools on how they can lobby the government during the eight-week consultation period for these proposals.

Patsalos said that business schools’ best bet is to argue for a specific objective. For example, for the government to cut the post-study work visa from two years to six months, rather than abolishing it altogether.

Charles Lewington, founder of Hanover Communications and former Conservative Party communications director, shared six pointers for a successful lobbying effort by UK business schools.

First, schools should speak with one voice. “This requires co-ordination through Universities UK or independently,” said Lewington. “Choose one or two schools to lead”.

Second, business schools will need detailed evidence in support of their position. “It’s no good making threats or issuing warnings without any substance... you need to commission someone to collate the evidence so that it passes muster with the Home Office and the Treasury.”

Third, schools must be clear about the technical solution they are seeking. Here, Lewington echoed Patsalos’ point about arguing for a specific reduction in the length of the visa.

Fourth, in addition to their “asks”, business schools need to position themselves as being part of the solution. “With the scale and speed of these spending cuts, everyone is pleading a special case. You need to think strategically about the contribution of business schools to the UK economy, or to driving growth in sectors other tan financial services.”

The Treasury is a key department to convince along with the Home Office said Lewington, because the Treasury is responsible for economic growth.

Fifth, business schools must agree on their brand. “If your brand is an expression of your values, you must collectively agree what those values are,” said Lewington. “What do you mean by excellence, what are your innovative products... how do you contribute to improving ethics in business?”

Finally, schools should be aware of the different political actors influencing this consultation. There are more MPs with business degrees and business experience now than there have been over the last 15 years.

Ministers other than Theresa May could also be useful allies: Business Secretary Vince Cable and David Willetts, Minister of State for Universities and Science, would support business schools as an important UK export, and as a destination for leading academics.

However business schools would have to be aware of the complexities of coalition politics, added Lewington. “Anything that appeals to Vince Cable may cause Theresa May to dig her heels in,” he said

The UK Business School Communications Conference was organised by BusinessBecause.com and Mana Communications, held at held at Cass Business School, and sponsored by Grenoble Ecole de Management and Google.