Delays in implementing the security measures of a Mali peace deal signed last year is making it harder for the army to counter resurgent jihadist groups, an army chief of the West African country said on Monday.

Islamist militants linked to al Qaeda who seized urban centers in Mali's desert north in 2012 were scattered by French forces a year later. But their insurgency is now intensifying and risks spilling into previously stable neighbors despite efforts by French and Malian forces to restore order.

In the latest sign of the growing dangers, a Swiss missionary was kidnapped from Timbuktu last week in the first known abduction of a Westerner since 2013. In November, 20 people were killed by militants in a luxury hotel in the once safe southern capital Bamako.

"The (security) situation is complicated by the lack of control and clarity on the movements of armed groups who signed the peace deal due to multiple delays in the implementation of DDR (Disarmament, Demobilisation and Reintegration)," said General Didier Dackouo, the army's number two official, in a speech before President Ibrahim Boubacar Keita at his palace.

An Algeria-brokered peace agreement was signed between the government and a medley of mostly secular northern armed groups in June and aimed to confine these fighters to barracks.

Security experts say this is necessary to allow counter-terror forces to distinguish between them and the desert-based jihadists who were never invited to the negotiating table.

But implementation of the deal has been hamstrung by squabbling between armed groups. Some of the signatory groups blame the government for delaying the process.

A 10,000-strong U.N. peacekeeping force in Mali, the most dangerous active peacekeeping mission in the world, late last month reported 28 attacks since September. Mali's army was also frequently targeted last year with 82 soldiers killed.

(Reporting by Adama Diarra; Writing by Emma Farge; Editing by Alistair Bell)