Colombo, Jun 5: A television network owned by the family of Sri Lankan Prime Minister Ranil Wickremesinghe was suspended by the island's telecom regulator today, worsening a power struggle in the fractious ruling coalition.

The closure of Telshan Network comes days after the station criticised President Maithripala Sirisena, who promised to end an era of draconian restrictions on the country's media.

Sirisena, who rules in an unsteady coalition with Wickremesinghe, has specific oversight of the telecom regulator and the decision has aggravated frictions between the men.

The network, owned by Wickremesinghe's eldest brother, was shut after the regulator accused its owners of defaulting on licence fees. The network has denied the allegations, insisting it has paid its dues.

Wickremesinghe's allies from his United National Party -- which backed Sirisena to election victory in 2015 -- protested the decision in parliament. "This is not something that we can accept. We are looking into this," said media minister Mangala Samaraweera, who said he was kept in the dark about the decision.

The closure is regarded as the first act of censorship of a broadcaster by Sirisena. In November he blocked Sri Lankans from being able to access the London-based Lanka E News website after it published an expose alleging graft in his office.

Soon after being elected, Sirisena had lifted the internet censorship and media restrictions used freely by his predecessor, strongman president Mahinda Rajapakse.

Some 17 journalists and media employees were killed in Sri Lanka during Rajapakse's regime, which also blocked pro-opposition websites. Sirisena's commanding position has waned as ties with his erstwhile ally have soured. The president has accused Wickremesinghe's party of corruption, while the UNP says Sirisena has obstructed reforms.

The gulf between the leaders has widened since their coalition was thumped in local elections in February, and hit a new low in April when Sirisena loyalists unsuccessfully sought to oust Wickremesinghe.