Many of last month's ethnic clashes that rocked Kyrgyzstan were centred in the Fergana Valley, a densely-populated and ethnically-diverse region, split between Uzbekistan, Kyrgyzstan and Tajikistan.

The borders were drawn up by Soviet planners in the 1920s and became a source of tension after the Soviet collapse in 1991.

Kyrgyzstan's Batken province, for example, is dotted with enclaves that belong to Uzbekistan and Tajikistan.

As Al Jazeera's Robin Forestier-Walker reports, the borders are fuelling mistrust between the communities.