A catalyst comprising:(a) an organometallic compound corresponding to the following general formula: RMe wherein R represents a saturated aliphatic or aromatic hydrocarbon radical having from 2 to 8 carbon atoms; and Me represents an alkali metal;(b) a compound corresponding to the following general formula: R'OMe' wherein R' represents a saturated aliphatic or aromatic hydrocarbon radical having from 2 to 8 carbon atoms; and Me' represents an alkali metal; and(c) a tertiary aliphatic triamine.A process for the preparation of said catalyst wherein components (a), (b) and (c) are dissolved, in any order, in an aliphatic or aromatic hydrocarbon and reacted at temperatures of from 0.degree. to 100.degree. C., and its use in the preparation of telomeric polybutadiene homo- or co-polymers.