China on Tuesday launched a spacecraft with a three-person crew to its under-construction space station amid intensifying competition with the United States.

The Shenzhou-15 spaceship carrying the aircraft was launched from the Jiuquan Satellite Launch Centre in northwest China.

It carried three astronauts -- Fei Junlong, Deng Qingming, and Zhang Lu.

Fei will be the commander of the mission, Ji Qiming, assistant to the director of the CMSA, told the media.

The launch was carried out with a Long March-2F carrier rocket.

The crew will stay in orbit for about six months, a period in which the construction of the low-orbit space station is expected to be completed.

After entering the orbit, the Shenzhou-15 spaceship will make a fast, automated rendezvous and dock with the front port of the space station's core module called Tianhe, Ji Qiming, assistant to the director of the China Manned Space Agency (CMSA), told the media on Monday.

This is the third manned mission launched by China to link up with its space station.

Two batches comprising three astronauts were flown to the space station, on a six-month mission each to build the orbiting station.

While one set of astronauts returned, another set of three astronauts is currently based in Tianhe.

As per the plans announced earlier by China, the space station is expected to be completed by the end of this year.

Once ready, China will be the only country to own a space station.

The International Space Station (ISS) of Russia is a collaborative project of several countries.

China Space Station (CSS) is also expected to be a competitor to the ISS built by Russia.

Observers say the CSS may become the sole space station to remain in orbit once the ISS retires in the coming years.