A scientist claims he has spotted water on Mars and believes it further strengthens his claim that NASA has already found signs of alien life on the planet.

Dr Barry DiGregorio, a researcher for the Buckingham Centre for Astrobiology, believes NASA Curiosity images show signs of alien trace fossils.

He theorised that the space agency did not explore the area adequately because it would dampen its plans to send humans there in the 2030s.

And Dr DiGregorio has claimed in his new book, Discovery on Vera Rubin Ridge: Trace Fossils on Mars, that he has identified liquid coming from the same images.

He told Daily Star Online: "I have enlarged these images using a technique called 3D photogrammetry.

Dr Barry DiGregio claims this could be liquid on Mars

"They both show part of a 4 millimetre sized section of the Martian rock NASA has named Haroldswick.

"If you look closely at the areas I have circled you can see what appears to be a liquid coming from the severed section and making contact with the host rock.

"I asked NASA about this and their explanation is that it must be 'sand'.

"Clearly it is not sand as you can see the individual sand grains scattered around the host rock. It has the appearance of some kind of liquid.

NASA believe Dr DiGregorio's sighting is simply sand

"Yet, why did NASA avoid examining it with Curiosity’s instruments? Or did they and are they keeping this data for themselves?"

Dr DiGregorio has previously speculated that the images could be a sign that "soft-bodied creatures" once roamed the Red Planet.

But Curiosity science team member at Imperial College London, Sanjeev Gupta, previously said: "These can form when salts become concentrated in water, such as in an evaporating lake."

Dr DiGregorio wants the images to be further assessed

And Abigail Fraeman, a fellow Curiosity team member, added in a statement: "These tiny 'V' shapes really caught our attention, but they were not at all the reason we went to that rock.

"We were looking at the colour change from one area to another. We were lucky to see the crystals.

"They're so tiny, you don't see them until you're right on them."

Daily Star Online has approached NASA for a response.