British taxpayers underwrote more than £100m worth of exports to Russia last year, including the sale of Airbus aircraft to an airline leasing firm linked to the state arms company Rosboronexport and owned by a Russian bank subjected to US sanctions.

The revelation that British government financial support is being extended to Russian deals is likely to embarrass David Cameron, who last week called for hard-hitting sanctions against the country's president, Vladimir Putin, and his government.

The credit insurance funding was provided UK Export Finance (UKEF), part of the Department for Business, Innovation and Skills, in the year to April 2014 and is shown in its latest annual report. It includes underwriting a £30m deal to help Airbus sell its planes to the Russian state-owned VEB Leasing. On its website, the company says it was "established at the initiative and with the participation of Rosoboronexport with the objective of raising product competitiveness of defence industry and civil engineering enterprises and facilitating their modernisation".

VEB Leasing's main shareholder is the Russian state development bank Vnesheconombank (VEB), which was subjected to US sanctions earlier this month.

Another £38m of government funding guarantee was extended to help EADS Astrium sell high-powered communication satellites to Russia Space Communication, which is part of the Russian communications ministry. The Russian government said the satellite technology was intended to provide TV and broadband to remote regions.

UKEF funding support is designed to help British companies obtain insurance and credit to help them export goods when traditional lenders may be afraid to provide financing. If the buyer goes bust or refuses to pay, the British taxpayer could be liable for the full value of the deal.

The revelation of UK taxpayer support for exports to Russia comes as the prime minister has called on Europe to impose sanctions on Russia after the downing of Malaysia Airlines flight MH17. Cameron called for action against Russian banks and airlines and for Putin's "cronies and oligarchs" to be blocked from accessing capital. He has also expressed frustration that other EU countries, including France and Germany, had failed to back his calls for the toughest possible sanctions against Moscow. "Those of us in Europe should not need to be reminded of the consequences of turning a blind eye when big countries bully smaller countries," he said last week.

George Osborne, the chancellor, has also called for tougher sanctions against Moscow. "Think of the economic hit of allowing international borders to be ignored, or allowing airliners to be shot down," he said. "That's a much greater hit for Britain and we're not prepared to allow that to happen." John Mann, a Labour member of the Commons Treasury committee, said the revelations that UK taxpayer funds were used to support Russian deals was highly embarrassing for Cameron. "It is totally hypocritical to be subsidising Russia while calling on Europe to introduce hard-hitting sanctions," he told the Guardian. "Cameron has the power to act on this, but he hasn't. It is tough talk but no action, and it is damaging the reputation of our country."

A government spokeswoman said: "The role of UKEF is to support UK exporters. Historically, some of those exporters have traded in Russia and our annual report for 2013/14 sets out the support we gave for UK exporters selling to Russia. This pre-dated the Ukraine crisis."

She declined to comment on whether UKEF had stopped supporting Russian exports in the wake of the crisis.

The UKEF has long supported British exports to Russia, with £215m of loan guarantees extended in the 2012-13 financial year. That included £53m to support the export of mining equipment to Siberian Coal Energy, Russia's largest coal company owned by the billionaire Andrey Melnichenko.