SAMARA, Russia, Aug 23 (Reuters) - Construction work on the World Cup stadium in the Russian city of Samara is about 30 days behind schedule, the company building the venue said on Wednesday, adding it would make up the lost time.

Work on the new 45,000-seat stadium, one of 12 that will host World Cup matches next summer, has been plagued by delays over the past months.

"We would have liked a faster construction pace," Sergei Ponomaryov, the deputy head of general contractor PSO Kazan, told reporters. "We have calculated that we are behind by about 30 days."

Ponomaryov said all major construction work at the venue would be finished by the end of the year, the initial deadline for its completion.

But on Wednesday cranes dominated the skyline above the venue and towering metal structures were supporting its roof.

The pitch also not been laid, unlike at some other venues being built for the tournament.

The governor of the Samara region, Nikolai Merkushkin, blamed the delay on unfavourable weather, including heavy rain in the Spring.

"In September we will be back on track," he said.

Deputy Prime Minister Vitaly Mutko said last month there was "no doubt" the venue would be ready by the end of the year, TASS news agency reported.

The Samara Arena will host four group stage matches, a match in the round-of-16 and a quarter final.

(Reporting by Gabrielle Ttrault-Farber; Editing by Mark Potter) ((Gabrielle.Tetrault-Farber@thomsonreuters.com;))