Eight peacekeepers have so far been confirmed dead and several others were wounded, he added in a statement.
In August 2017, five MINUSMA security guards, one member of the Mali National Police and one civilian contractor working for MINUSMA were killed during an attack on MINUSMA headquarters in Timbuktu.
Ten UN peacekeepers from Chad have been killed in an attack by suspected Islamist militants in northern Mali, the UN says.
The attack happened at the Aguelhok base in northern Mali early this morning, according to a source close to the United Nations force in the country.
Special Representative of the Secretary-General in Mali Mahamat Saleh Annadif said: "This complex and cowardly attack illustrates the terrorists' determination to sow chaos; it demands a robust, immediate and concerted response from all forces to wipe out the danger of terrorism in the Sahel".
Pep Guardiola demands more from Manchester City despite 100-goal milestone
We have to go to Old Trafford too and try to win there. "We can do what we can do but for Liverpool v United we can do nothing". Huddersfield made six changes for the game but did manage to match reigning English champions City early on.
Below-zero wind chills keeping central IN on ice
Today's high will only top out at -17 C - that's below the average low (-15.7 C) for this time of the year. With highs in the mid 30s to mid 40s by midday, most spots will end up in the 20s by 5pm.
Financial crash WARNING: Global economy growth forecast SLASHED ahead of Davos 2019
The figures from the National Bureau of Statistics drags full-year growth down to 6.6 percent, the slowest annual pace since 1990. It also attributed the grim outlook to slowing economic growth in Europe, especially Germany and Italy.
Militants have regularly attacked United Nations and Malian troops since then.
Mali, the eighth largest country in Africa and one of the poorest in the world, has been struggling to return to stability after al-Qaeda-linked fighters took control of the northern areas of the country in early 2012, prompting France to intervene militarily.
On Sunday, France's Defense Minister Florence Parly told French radio that the G5 Sahel anti-jihadist force in the region was resuming its operations.
A peace deal between the government and armed groups was signed in 2015, but its implementation has been slow, while attacks continue in central and northern parts of the country. The G5 force comprises contingents from Mali, Mauritania, Niger, Burkina Faso and Chad.
And Washington renewed its warning that it would push for changes to the peacekeeping mission in Mali, possibly a major drawdown, if there was no progress.