This NASA/Boeing handout image shows an artist concept of the CST-100 Starliner in Earth's orbit

Boeing will relaunch an uncrewed test flight of its Starliner spaceship, the company said Monday, after an earlier mission failed due to multiple glitches.

The aim of Starliner is to take US astronauts to the International Space Station.

A test run in December was ended early when the spacecraft failed to engage its thrusters on time.

Another problem was intermittent space-to-ground communications, impeding the flight control team's ability to command and control the vehicle.

"We have chosen to refly our Orbital Flight Test to demonstrate the quality of the Starliner system," Boeing said.

"Flying another uncrewed flight will allow us to complete all flight objectives and evaluate the performance of the second Starliner vehicle at no cost to the taxpayer.

"We will then proceed to the tremendous responsibility and privilege of flying astronauts to the International Space Station."

A Boeing spokeswoman was quoted by CBS News as saying the company hopes to fly the mission "in the fall of 2020."

Starliner's first crewed had been scheduled for early 2020.

The delay puts the Starliner mission further behind tech entrepreneur Elon Musk's SpaceX, which NASA said last month was preparing to send astronauts to the ISS in May.

NASA has committed to pay $8 billion to Boeing and SpaceX, which will deliver six trips carrying four astronauts each from now to 2024.

NASA sent up its last space shuttle in 2011. Since then it has relied on Russian rockets to get American to the ISS.

Starliner's failure was the latest serious setback for Boeing, which is still reeling from two fatal crashes of its 737 Max aircraft.