(Bloomberg) – India has surged to become the second-biggest supplier of restricted critical technologies to Russia, US and European officials said, highlighting the challenge in efforts to choke off exports fueling President Vladimir Putin’s war machine.

Indian exports of restricted items such as microchips, circuits and machine tools surpassed $60 million in both April and May, about double from earlier months this year, and leaped to $95 million in July, according to the officials, who asked not to be identified discussing private assessments. India is exceeded only by China.

Even more frustrating to Ukraine’s allies, some of them said, is that envoys who raise the issue have received little response from their Indian counterparts. India’s Ministry of External Affairs declined to comment when asked about the trend.

The most recent data means almost a fifth of the sensitive technology that goes into Russia’s military-industrial complex got there via India, the officials said.