BASF’s oil and gas subsidiary, Wintershall, used hydraulic fracturing for many years to extract conventional gas but has been prevented from doing so recently because of rules against fracking.

BASF and other companies also want the government to authorize shale gas production as a possible tool for lowering energy costs.

“It is necessary to find out more about the potential that shale gas actually has in Germany. Today, nobody knows whether shale gas development makes sense,” the company said.

BASF has been investing in plants in North America to take advantage of the low gas prices there.

Should Germany move ahead with exploration of shale gas, it would join Britain as one of two countries in Western Europe permitting energy operators to look for so-called unconventional gas and oil. Britain is encouraging shale exploration in an effort to replace declining oil and gas output from the North Sea and to build up domestic sources of supply for industry, particularly power generation.

If the energy industries in these two large European countries were to succeed in producing shale gas without serious environmental consequences, then pressure would build on other countries, including France, which is also thought to have significant shale resources, to change tack.

The guidelines being discussed by Ms. Merkel’s government would require environmental audits from two independent authorities and would impose a ban on drilling in areas where water is protected, according to a letter written by Sigmar Gabriel, the economy and energy minister, to a member of Parliament.

In the letter, obtained by the German news agency DPA, Mr. Gabriel said he intended to put the law to a vote in Parliament, where Ms. Merkel’s conservatives, together with the Social Democrats, hold a comfortable majority. “The goal is to finalize these drafts in the coming weeks,” the letter says.