The Ministry of Defence is considering imposing a ceiling on the number of foreigners recruited for the UK's armed forces because senior officers fear that the growing influx of overseas volunteers could dilute the essential "Britishness" of the Army, The Herald can reveal.

The Ministry of Defence is considering imposing a ceiling on the number of foreigners recruited for the UK's armed forces because senior officers fear that the growing influx of overseas volunteers could dilute the essential "Britishness" of the Army, The Herald can reveal.

Top brass are also worried about the perception that they are encouraging the employment of mercenaries at a time when they want the services to reflect British "norms and values".

Including 3500 Gurkhas and more than 7000 Commonwealth and other foreigners already in the ranks, more than 10% of current Army manpower is composed of foreign nationals.

The number of overseas soldiers who enlisted in the Army, Navy and RAF rose by 790 last year to 7240. By comparison, the famous French Foreign Legion employs 7600 non-French troops.

Britain's unofficial "legion" includes 2030 Fijians, 600 Zimbabweans and 460 from the tiny Caribbean island state of St Vincent and the Grenadines.

There are also 880 from South Africa, 140 from Kenya and 170 from Australian and New Zealand. Another 80 are from Canada. Almost one-in-10 of the soldiers in the Royal Regiment of Scotland is Fijian.

Political or social unrest in some countries and high unemployment, almost 25% in most Caribbean islands, appear to be the main driving forces behind the enlistments.

The number of Caribbean volunteers has soared, with the St Vincent contingent rising from 280 in 2006 to 460 last year. South African volunteers rose from 720 to 880, while Trinidad and Tobago's contribution to British numbers increased from 70 to just over 100. Zimbabwe, now in economic and political meltdown, produced a 20% rise.

With almost every battalion in the Army an average of 70 to 90 men below frontline "bayonet strength", the influx of willing volunteers means there are foreigners in most units, with the highest concentration in the hard-pressed infantry.

The MoD admits the Army is 3800 men below complement, a shortfall worsened by the number of experienced soldiers of all ranks choosing to leave, largely because of the family pressures resulting from repeated combat tours in Iraq and Afghanistan.

The main problem is that without the overseas contingent, the already overstretched Army would be unable to sustain the 7800-strong garrison in Afghanistan and the 4100 in Iraq.

The MoD's quarterly report, published earlier this week, admitted it could not meet government readiness targets as a result of the continuing tempo of operations.

Forces are supposed to ensure that at least 73% of units have no "serious or critical weaknesses". A total of 58% barely met that target in their peacetime readiness levels, falling to just 53% in the last three months of 2007.

The MoD is supposed to be able to generate forces which can be "deployed, sustained and recovered at the scales of effort required to meet the government's strategic objectives".

Armed Forces Minister Bob Ainsworth yesterday confirmed the MoD review: "We are proud to recruit high-quality recruits from countries with close historical and political ties.

"While no decision has been taken to introduce a cap on Commonwealth and Republic of Ireland citizens, we are looking at the rising levels within the armed forces."