Mobile operator Veon reported a 5.6% rise in second-quarter revenue on Thursday, driven by a rising number of subscribers and Ukrainian refugees' data usage, coupled with an inflationary pricing strategy.

Although the firm has been facing geopolitical uncertainties amid the Russia-Ukraine conflict, which investors feared could put pressure on cash flow as both countries account for its most profitable markets, it still saw a strong ramp-up in revenues in the three months ending in June.

The Amsterdam-listed company recorded revenues of $2 billion in the three months to June 30, compared with $1.9 billion a year earlier.

In Ukraine, where Veon operates the biggest cell phone provider Kyivstar, the 4G customer base grew 11.9%, while in Russia, its biggest market where it operates the Beeline mobile brand, reported a revenue increase of 12.2%.

"For us Ukraine is a network that needs to run at all costs," Chief Executive Officer Kaan Terzioglu said in an interview. "Six million Ukrainians have been out of the country in roaming conditions and their utilization of voice and data has increased 16 times during this time."

He noted that two employees have been killed in Ukraine because of the conflict.

Russia's capital controls are impacting international cash transfers but Terzioglu said Veon's operations self-sufficiency allows the company to finance activity at its country units through money earned locally.

Terzioglu said that the company, which reported $2.4 billion in cash, does not plan to take money out of Russia.

"They will be very cash rich, local operation," he said.

The company said it will continue to monitor the situation in Russia and Ukraine and assess the need for potential impairment charges.

(Reporting by Diana Mandia and Alizee Degorce in Gdansk; Additional reporting by Supantha Mukherjee in Stockholm; Editing by Rashmi Aich and Christian Schmollinger)