National Aeronautics and Space Administration's (Nasa) on Friday insisted that the first astronauts to fly Boeing's troubled Starliner are not "stranded" at the International Space Station despite no clear timeframe for bringing them home. 

In an attempt to paint a positive picture after weeks of negative headlines, Nasa’s commercial crew programme manager in a press conference on Friday said, "Butch and Suni are not stranded in space", AFP reported. 

He added that the pair were "enjoying their time on the space station" and "our plan is to continue to return them on Starliner and return them home at the right time". 

However, when asked about their return date, he said, "We don't have a targeted (landing) date today."

The Boeing Starliner was initially set to return from the International Space Station on June 14, but was pushed back for June 26. However, now the return is being further pushed back.

After years of delays, Boeing's Starliner capsule lifted off from Florida's Cape Canaveral Space Force Station on June 5.

According to reports, one helium leak was known prior to the launch, however, more leaks emerged during the 25-hour flight.

Separately, some of Starliner's thrusters that provide fine manoeuvring initially failed to kick in, delaying docking. Engineers are not sure why Starliner's computer "deselected" these thrusters, though they were able to restart all but one of them.

While talking about the negative comments, Boeing's Vice President and Programme Manager of its Commercial Crew Programme, Mark Nappi said, "It is pretty painful to read the things that are out there. We've gotten a really good test flight that's been accomplished so far, and it's being viewed rather negatively."