**Exhibit 31.1****CERTIFICATION**I, Mark R. Keller, certify that:     1. I have reviewed this Quarterly Report on Form 10-Q of Republic Property Trust;     2. Based on my knowledge, this report does not contain any untrue statement of a material factor omit to state a material fact necessary to make the statements made, in light of thecircumstances under which such statements were made, not misleading with respect to the periodcovered by this report;     3. Based on my knowledge, the financial statements, and other financial information includedin this report, fairly present in all material respects the financial condition, results ofoperations and cash flows of Republic Property Trust as of, and for, the periods presented in thisreport;     4. Republic Property Trust’s other certifying officer and I are responsible for establishingand maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules13a-15(f) and 15d-15(f)), for Republic Property Trust and have:     a) Designed such disclosure controls and procedures, or caused such disclosure controls andprocedures to be designed under our supervision, to ensure that material information relating toRepublic Property Trust, including its consolidated subsidiaries, is made known to us by otherswithin those entities, particularly during the period in which this report is being prepared;     b) Designed such internal control over financial reporting, or caused such internal controlover financial reporting to be designed under our supervision, to provide reasonable assuranceregarding the reliability of financial reporting and the preparation of financial statements forexternal purposes in accordance with generally accepted accounting principles;     c) Evaluated the effectiveness of Republic Property Trust’s disclosure controls andprocedures and presented in this report our conclusions about the effectiveness of the disclosurecontrols and procedures, as of the end of the period covered by this report based on suchevaluation; and     d) Disclosed in this report any change in Republic Property Trust’s internal control overfinancial reporting that occurred during Republic Property Trust’s most recent fiscal quarterthat has materially affected, or is reasonably likely to materially affect, Republic PropertyTrust’s internal control over financial reporting; and     5. Republic Property Trust’s other certifying officer and I have disclosed, based on our mostrecent evaluation of internal control over financial reporting, to Republic Property Trust’sauditors and the audit committee of Republic Property Trust’s board of directors (or personsperforming the equivalent functions):     a) All significant deficiencies and material weaknesses in the design or operation ofinternal control over financial reporting which are reasonably likely to adversely affectRepublic Property Trust’s ability to record, process, summarize and report financial information;and     b) Any fraud, whether or not material, that involves management or other employees who havea significant role in Republic Property Trust’s internal control over financial reporting.         By:      /s/ Mark R. Keller    Name:  Mark R. Keller    Title:  Chief Executive Officer (Principal Executive Officer)   Date: August 6, 2007