After several months of discussions, the Social Democratic Party on Tuesday gave up efforts to persuade the ruling Liberal Democratic Party to implement ahead of schedule a ban on corporate and group donations to individual politicians.The proposed ban is to take effect in 2000 under the political funds control law. The SDP, one of the LDP's two non-Cabinet allies, had maintained that the ban should be moved up to put an end to a series of corruption scandals involving politicians and businesses. "Matters related to the introduction of the ban will not be included in the ruling bloc's agenda on political ethics," SDP Secretary General Shigeru Ito told reporters.He made the remark after a meeting with Koichi Kato and Hiroyuki Sonoda, Ito's LDP and New Party Sakigake counterparts. Sakigake, another LDP ally, has also been reluctant to accept the ban, saying that it would be difficult for members of the party to do without such donations.However, Ito indicated that the SDP will not leave the ruling bloc in spite of SDP leader Takako Doi's repeated remarks that the SDP will make "an important decision" if the LDP ignores key SDP policies, which include an early ban on such donations.The heads of the three parties, Prime Minister Ryutaro Hashimoto, Doi and Sakigake chief Akiko Domoto, will meet this evening to confirm they will continue work over the next three months on other measures to help establish political ethics, Ito said.