Mobilink is the only one of the Pakistan's four 3G licensees yet to launch commercial services and rumour has it that the country's telecoms regulator is blocking it from doing so on technical grounds.

The Pakistan Telecommunication Authority (PTA) is not satisfied with Mobilink's quality of service (QoS) and has therefore barred it from launching services, according to a local press report. The issue is linked to the provisioning of services on users' smartphones, Pakistan's Daily Times claimed at the weekend, citing unnamed sources.

As such, Pakistan's largest mobile operator has extended its period of free 3G trials while its rivals are able to sell commercial services, the paper added.

Mobilink has not confirmed the report. A company spokesperson told the paper that he was not aware of a PTA block.

He added that Mobilink will launch commercial services "soon".

Four of Pakistan's five mobile network operators took part in the country's 3G and 4G licensing process in April. All four came away with 2.1-GHz spectrum earmarked for 3G services, but only China Mobile acquired 1800-MHz spectrum for 4G.

The process raised a total of $1.1 billion (€817 million), including the $210 million China Mobile paid for its 4G airwaves.

Ufone was first to market in May while Telenor followed suit in early June. China Mobile's Zong launched its 3G services a couple of weeks ago.