LONDON, ENGLAND - Governments and central banks must act "decisively" to calm the current financial turmoil, British finance minister Alistair Darling said Thursday, shortly after central banks intervened.

"The key is that governments, central banks, the regulators act decisively and quickly when these problems arise," he said, after the Bank of England announced liquidity-boosting measures backed by other central banks including the US Federal Reserve, the European Central Bank and the Bank of Japan.

"The key thing, especially at this time, is to maintain stability of the banking system. That is paramount," he told BBC radio.

"We are going through a truly exceptional difficult time in relation to banks and other financial institutions," he added.

Specifically he supported the takeover by British bank Lloyds TSB of distressed rival Halifax Bank of Scotland (HBOS) in a 12.2-billion-pound (15.4 billion euro, 21.8 billion dollar) deal.

The landmark all-share deal, effectively a rescue plan for Britain's biggest mortgage lender, comes after HBOS shares plummeted in recent trading following days of global economic crisis.

"I think it was absolutely necessary," he said.

"For some times, it's been obvious to us that there's been concerns about HBOS and for a long time... we've been monitoring the position.

"At the beginning at this week, it was quite clear that the situation was becoming more difficult and bluntly, as I think everybody recognizes, the best possible outcome was for Lloyds and HBOS to come together."

"As I said a couple of days ago, I've made it very clear that we would do everything that we possibly can that was appropriate to insure the stability of the financial system, so we did everything we could to help," he added.