According to the source, an official confirmation of the delay is expected to be announced shortly.
"The launch will be postponed due to two technical issues, which are not in the scope of Russia's responsibility," the source said.
"There's nothing alarming in the delay as the 'launch window' allows us to carry out the launch on March 14 and deliver the spacecraft to Mars, with the help of Proton, on time," the source stressed.
In 2012, the European Space Agency and the Russian Federal Space Agency Roscosmos agreed to develop the so-called ExoMars program, with the objective of investigating the environment on Mars and finding out whether life has ever existed on the planet.
As published on the European Space Agency's website, two missions are planned within the ExoMars program for 2016-2018. In 2016, the ExoMars project will launch an orbital probe to Mars, followed by a landing on the Martian surface by a lander module. In 2018, a Mars rover probe is expected to explore the surface of the planet.
After the European Union introduced sanctions against Russia over its alleged role in the Ukrainian internal crisis, concerns mounted that Europe-Russia collaboration on Mars exploration could be hampered.