lighting fires under the government

[suprunp]

America was pushing Japan to open its financial markets. Morgan Stanley and Merrill Lynch were lighting fires under the government in search of new sources of profit.
(H. Murakami; 1Q84)

What does it exactly mean?

Thanks.

[SoothingDave]

If I lit a fire under you, would you move? Probably yes, and quickly.

To light a fire under someone/something is to do everything you can to make them go into action.