I've had a quick Google, but can't find anything that isn't somewhat tenuous, but I was wondering if there were ever any links between the IRA and the USSR? Did the Soviets ever provide money or weapons like Libya did?
Similarly, the IRA has clearly worked closely with other members of the eastern block - there's this amusing story about the IRA's trip to North Korea.
Thinking of the international situation at the time it seems like they would have been fairly natural allies - yet I can't find anything to suggest they were? If they didn't work together, is there any reason why this was?
They did have a secret agreement that started in 1925, although Stalin was always sceptical of the IRA and the agreement was kept secret to the extent that even the British and American intelligence services had little idea about the extent of it.
The main part of the argument was that the IRA would 'spy' or try to gain intelligence from Britain in return for a £500 per month payment. The IRA also had to support the aims of the Soviet Union, for example they ended up sending equipment to China.
The payment was also cut in 1927 down to £100 per month which led to a disaster within the IRA as they simply could not run on that amount of money. The Soviets did end up paying £1,000 as a one off to keep the IRA going.
The soviets were also reluctant to send weapons as they did not want them to be traced back and cause further tensions with the Soviet Union.
I would highly recommend this article as well as a 'Decoding the IRA' by Thomas Mahon and James Gillogly if you can get your hands on a copy.
Soviet Bloc supported the Marxist 'Official IRA' and its political front group, the self-styled 'Workers Party', which were violently hostile to the Provisional IRA. This group went underground in the 1980s/90s and completely infiltrated the Irish Labour Party, the trade unions, RTE and Ireland's news media. Supposedly, they're still heavily armed with Soviet weaponry; here's a story from today: http://www.independent.ie/irish-news/news/official-ira-hid-5000-ak47s-in-secret-bunkers-31267061.html