The Bureau of Internal Revenue (BIR) placed on Thursday under close monitoring payments made by the country's more than 1,000 top corporations.

Revenue Commissioner Joel Tan-Torres said he came out with the big ticket items (BTI) memorandum to improve enforcement and compliance by taxpayers.

It included payments of P200 million and more for single transactions.

He instructed Large Taxpayers (LTs) Assistant Commissioners Zeny Garcia and Nestor Valeroso to implement the directive.

The LTs collects more than 60 percent of the annual total take of the BIR, or roughly around P490 billion of the 2010 collection target of P830 billion.

The BIR chief instructed the two LTs officials to monitor occurrences of BTI transactions publish in the media, websites of taxpayers as well as the disclosure action taken by the Securities and Exchange Commission (SEC), Bangko Sentral ng Pilipinas (BSP) and other government agencies.

After accessing the data, Tan-Torres instructed tax collectors to send an access to records letters to these taxpayers, five days after the transanction was made or discovered.

He said a letter of authority, or a subpoena should be issued after the said taxpayers failed to answer access to record letter.

He said that upon receipt of the requested documents, tax collectors should evaluate any tax consequences to ascertain the correctness and timeliness of the tax payment.